summaryrefslogtreecommitdiff
path: root/Master/texmf-dist/source/latex/l3build/l3build.dtx
blob: a68f9d6330eec462b864a03f2f2eb82e7f81ba74 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
% \iffalse
%%
%% File l3build.dtx (C) Copyright 2014-2015 The LaTeX3 Project
%%
%% It may be distributed and/or modified under the conditions of the
%% LaTeX Project Public License (LPPL), either version 1.3c of this
%% license or (at your option) any later version.  The latest version
%% of this license is in the file
%%
%%    http://www.latex-project.org/lppl.txt
%%
%% This file is part of the "l3build bundle" (The Work in LPPL)
%% and all files in that bundle must be distributed together.
%%
%% The released version of this bundle is available from CTAN.
%%
%% -----------------------------------------------------------------------
%%
%% The development version of the bundle can be found at
%%
%%    http://www.latex-project.org/svnroot/experimental/trunk/
%%
%% for those people who are interested.
%%
%%%%%%%%%%%
%% NOTE: %%
%%%%%%%%%%%
%%
%%   Snapshots taken from the repository represent work in progress and may
%%   not work or may contain conflicting material!  We therefore ask
%%   people _not_ to put them into distributions, archives, etc. without
%%   prior consultation with the LaTeX Project Team.
%%
%% -----------------------------------------------------------------------
%%
%
%
%<*driver>
\RequirePackage{expl3}
\def\ExplFileName{l3build}
\def\ExplFileDescription{L3 Regression test suite}
\def\ExplFileDate{2015/09/27}
\def\ExplFileVersion{6111}
\documentclass[full]{l3doc}
\renewcommand\partname{Part}
\usepackage{multicol,needspace}

\makeatletter
\addtolength\columnsep{1em}
\renewcommand\columnseprule{0.4pt}
\def\@starttoc#1{%
  \begin{multicols}{2}
  \small
  \makeatletter
  \@input{\jobname.#1}%
  \expandafter\newwrite\csname tf@#1\endcsname
  \immediate\openout \csname tf@#1\endcsname \jobname.#1\relax
  \@nobreakfalse
  \end{multicols}}
\makeatother

\newenvironment{buildcmd}[1]{%
  \bigskip\par\noindent\hspace{-\parindent}%
  \fbox{\ttfamily \textcolor[gray]{0.5}{\$} texlua build.lua #1}%
  \nopagebreak\smallskip\nopagebreak\par\nopagebreak\noindent\ignorespaces
 }
 {}
\makeatletter
\newcommand\luavar[1]{\@ifundefined{lua_#1}{\ERROR}{\texttt{\@nameuse{lua_#1}}}}
\newcommand\luavarset[3]{\@namedef{lua_#1}{#2}}
\newcommand\luavarseparator{}
\makeatother
\def\allluavars{
\luavarset{module}{""}{The name of the module.}
\luavarset{bundle}{""}{The name of the bundle in which the module belongs.}
\luavarset{ctanpkg}{bundle}{Name of the bundle on CTAN}
\luavarseparator
\luavarset{modules}{\{~\}}{The list of all modules in a bundle (when not auto-detecting)}
\luavarset{exclmodules}{\{~\}}{Directories to be excluded from automatic module detection}
\luavarseparator
\luavarset{maindir}     {"."}{The top level directory for this module or bundle.}
\luavarset{supportdir}  {maindir .. "/support"}     {Where copies of files to support check/doc compilation are stored.}
\luavarset{testfiledir} {maindir .. "/testfiles"}   {Where the tests are.}
\luavarset{testsuppdir} {testfiledir .. "/support"} {Where support files for the tests are.}
\luavarseparator
\luavarset{localdir}   {maindir .. "/build/local"}  {Generated folder where support files are placed to allow \enquote{sandboxed} \TeX{} runs.}
\luavarset{testdir}    {maindir .. "/build/test"}   {Generated folder where tests are run.}
\luavarset{typesetdir} {maindir .. "/build/doc"}    {Generated folder where typesetting is run.}
\luavarset{unpackdir}  {maindir .. "/build/unpack"} {Generated folder where unpacking occurs.}
\luavarset{distribdir} {maindir .. "/build/distrib"}{Generated folder where the archive is created.}
\luavarset{ctandir}    {distribdir .. "/ctan"}      {Generated folder where files are organised for CTAN.}
\luavarset{tdsdir}     {distribdir .. "/tds"}       {Generated folder where files are organised for a TDS.}
\luavarset{tdsroot}    {"latex"}{Root directory of the TDS structure for the bundle/module to be installed into.}
\luavarseparator
\luavarset{bibfiles}        {\{"*.bst"\}}{\BibTeX{} database files.}
\luavarset{binaryfiles}     {\{"*.pdf", "*.zip"\}}
                            {Files to be added in binary mode to zip files.}
\luavarset{bstfiles}        {\{"*.bst"\}}{\BibTeX{} style files.}
\luavarset{checkfiles}      {\{~\}}{Extra files unpacked purely for tests}
\luavarset{checksuppfiles}  { }{Files needed for performing regression tests.}
\luavarset{cmdchkfiles}     {\{~\}}{Files need to perform command checking (\cls{l3doc}-based documentation only).}
\luavarset{cleanfiles}      {\{"*.log", "*.pdf", "*.zip"\}}{Files to delete when cleaning.}
\luavarset{demofiles}       {\{~\}}{Files which show how to use a module.}
\luavarset{docfiles}        {\{~\}}{Files which are part of the documentation but should not be typeset.}
\luavarset{excludefiles}    {\{"*\string~"\}}            {Files to ignore entirely (default for Emacs backup files).}
\luavarset{installfiles}    {\{"*.sty"\}}         {Files to install to the \TeX{} tree and similar tasks.}
\luavarset{makeindexfiles}  {\{"*.ist"\}}{MakeIndex files to be included in a TDS-style zip}
\luavarset{sourcefiles}     {\{"*.dtx", "*.ins"\}}{Files to copy for unpacking.}
\luavarset{textfiles}       {\{"*.md", "*.txt"\}}{Plain text files to send to CTAN as-is.}
\luavarset{typesetfiles}    {\{"*.dtx"\}} {Files to typeset for documentation.}
\luavarset{typesetsuppfiles}{\{~\}}       {Files needed to support typesetting when \enquote{sandboxed}.}
\luavarset{unpackfiles}     {\{"*.ins"\}} {Files to run to perform unpacking.}
\luavarset{unpacksuppfiles} {\{~\}}       {Files needed to support unpacking when \enquote{sandboxed}.}
\luavarseparator
\luavarset{lvtext} {".lvt"} {Extension of test files.}
\luavarset{tlgext} {".tlg"} {Extension of test file output.}
\luavarset{lvtext} {".lve"} {Extension of auto-generating test file output.}
\luavarset{logext} {".log"} {Extension of checking output, before processing it into a \texttt{.tlg}.}
\luavarseparator
\luavarset{checkdeps}   {\{~\}} {List of build unpack dependencies for checking.}
\luavarset{typesetdeps} {\{~\}} {\dots for typesetting docs.}
\luavarset{unpackdeps}  {\{~\}} {\dots for unpacking.}
\luavarseparator
\luavarset{checkengines}{\{"pdftex", "xetex", "luatex"\}} {Engines to check with \texttt{check} by default.}
\luavarset{stdengine}    {"pdtex"} {Engine to generate \texttt{.tlg} file from.}
\luavarset{checkformat}  {"latex"} {Format to use for tests.}
\luavarseparator
\luavarset{typesetexe} {"pdflatex"} {Executable for compiling \texttt{doc(s)}.}
\luavarset{unpackexe}  {"tex"}      {Executable for running \texttt{unpack}.}
\luavarset{zipexe}     {"zip"}      {Executable for creating archive with \texttt{ctan}.}
\luavarseparator
\luavarset{checkopts}  {"-interaction=batchmode"}  {Options based to engine when running checks.}
\luavarset{cmdchkopts} {"-interaction=batchmode"}  {Options based to engine when running command checks.}
\luavarset{typesetopts}{"-interaction=nonstopmode"}{Options based to engine when typesetting.}
\luavarset{unpackopts} {""}                        {Options based to engine when unpacking.}
\luavarset{zipopts}    {"-v -r -X"}                {Options based to zip program.}
\luavarseparator
\luavarset{checksearch}  {true}  {Look in \texttt{tds} dirs for checking?}
\luavarset{typesetsearch}{true}  {Look in \texttt{tds} dirs for typesetting docs?}
\luavarset{unpacksearch} {true}  {Look in \texttt{tds} dirs for unpacking?}
\luavarseparator
\luavarset{glossarystyle}{"gglo.ist"}{MakeIndex style file for glossary/changes creation}
\luavarset{indexstyle}   {"gind.ist"}{MakeIndex style for index creation}
\luavarseparator
\luavarseparator
\luavarset{biberexe}     {"biber"}    {Biber executable}
\luavarset{biberopts}    {""}         {Biber options}
\luavarset{bibtexexe}    {"bibtex8"}  {\BibTeX{} executable}
\luavarset{bibtexopts}   {"-W"}       {\BibTeX{} options}
\luavarset{makeindexexe} {"makeindex"}{MakeIndex executable}
\luavarset{makeindexopts}{""}         {MakeIndex options}
\luavarseparator
\luavarset{asciiengines}{\{"pdftex"\}}{Engines which should log as sure ASCII}
\luavarset{checkruns}   {1}           {How many times to run a check file before comparing the log.}
\luavarset{packtdszip}  {false}       {Build a TDS-style zip file for CTAN?}
\luavarset{scriptname}  {"build.lua"} {Name of script used in dependencies.}
\luavarset{typesetcmds} {""}          {Instructions to be passed to \TeX{} when doing typesetting.}
}
\allluavars
\newcommand\luavartypeset{%
  \begingroup
  \frenchspacing
  \renewcommand\luavarset[3]{
    \texttt{##1} & \texttt{##2} & ##3 \\
  }
  \renewcommand\luavarseparator{\midrule}
  \setlength\LTleft{-0.21\linewidth}
  \begin{longtable}{@{}%
    >{\small}
    p{0.18\linewidth}
    @{\hspace{0.03\linewidth}}
    >{\footnotesize\hangindent=1em}
    p{0.34\linewidth}
    @{\hspace{0.03\linewidth}}
    >{\small\raggedright\arraybackslash}
    p{0.63\linewidth}
    @{}}
  \toprule
  Variable & Default & Description \\
  \midrule\endhead
  \allluavars
  \bottomrule
  \end{longtable}
  \endgroup
}

\newcommand\code{\texttt}
\newcommand\var{\texttt}

\usepackage[procnames]{listings}
\lstset{
    basicstyle=\ttfamily\small,
    numbers=left,
    numberstyle={\tiny\color[gray]{0.4}},
}

\usepackage{shortvrb}
\usepackage{enumitem}
\usepackage{longtable}
\MakeShortVerb\|
\begin{document}
  \DocInput{\jobname.dtx}
\end{document}
%</driver>
% \fi
%
% \title{^^A
%   The \pkg{l3build} package\\ Checking and building packages^^A
%   \thanks{This file describes v\ExplFileVersion,
%      last revised \ExplFileDate.}^^A
% }
%
% \author{^^A
%  The \LaTeX3 Project\thanks
%    {^^A
%      E-mail:
%        \href{mailto:latex-team@latex-project.org}
%          {latex-team@latex-project.org}^^A
%    }^^A
% }
%
% \date{Released \ExplFileDate}
%
% \maketitle
% \tableofcontents
%
% \begin{documentation}
%
% \section{The \pkg{l3build} system}
%
% \subsection{Introduction}
%
% The \pkg{l3build} system is a Lua script for building \TeX{} packages, with particular emphasis on regression testing.
% It is written in cross-platform Lua code, so can be used by any modern \TeX{} distribution with the |texlua| interpreter.
% A package for building with \pkg{l3build} can be written in any \TeX\ dialect; its defaults are set up for \LaTeX\ packages written in the DocStrip style. (Caveat: minimal testing has yet been performed for non-\LaTeX{} packages.)
%
% Test files are written as standalone \TeX{} documents using the |regression-test.tex| setup file; documentation on writing these tests is discussed in Section~\ref{sec:writing-tests}.
%
% The |l3build.lua| script is not designed to be executed directly; each package will define its own |build.lua| script as a driver file which both sets variables (such as the name of the package) and then calls the main |l3build.lua| script internally.
%
% \pagebreak[2]
% A standard package layout might look something like the following:
% \begin{Verbatim}[fontsize=\small]
%  abc/
%      abc.dtx
%      abc.ins
%      build.lua
%      README.md
%      support/
%      testfiles/
% \end{Verbatim}
% Most of this should look fairly self-explanatory.
% The top level |support/| directory (optional) would contain any necessary files for compiling documentation, running regression tests, and so on.
%
% The \pkg{l3build} system is also capable of building and checking \emph{bundles} of packages.
% To avoid confusion, we refer to either a standalone package or a package within a bundle as a \emph{module}.
%
% For example, within the \LaTeX3 project we have the \textsf{l3packages} bundle which contains the \textsf{xparse}, \textsf{xtemplate}, etc., modules.
% These are all built and distributed as one bundle for installation, distribution \emph{via} CTAN and so forth.
%
% Each module in a bundle will have its own build script, and a bundle build script brings them all together.
% A standard bundle layout would contain the following structure.
% \begin{Verbatim}
% mybundle/
%          build.lua
%          support/
%          yyy/                    zoo/
%              build.lua               build.lua
%              README.md               README.md
%              testfiles/              testfiles/
%              yyy.dtx                 zoo.dtx
%              yyy.ins                 zoo.ins
% \end{Verbatim}
% All modules within a bundle must use the same build script name.
%
% In a small number of cases, the name used by CTAN for a module or bundle is
% different from that used in the installation tree. For example, the \LaTeXe{}
% kernel is called \pkg{latex-base} by CTAN but is located inside
% \texttt{\meta{texmf}/tex/latex/base}. This can be handled by using
% \var{ctanpkg} for the name required by CTAN to override the standard
% value.
%
% The |testfiles/| folder is local to each module, and its layout consists of a series of regression tests with their outputs.
% \begin{Verbatim}
% testfiles/
%           test1.lvt
%           test1.tlg
%           ...
%           support/
%                   my-test.cls
% \end{Verbatim}
% Again, the |support/| directory contains any files necessary to run some or all of these tests.
%
% When the build system runs, it creates a directory |build/| for various unpacking, compilation, and testing purposes.
% For a module, this build folder can be in the main directory of the package itself, but for a bundle it should be common for the bundle itself and for all modules within that bundle.
% A |build/| folder can be safety deleted; all material within is re-generated for each command of the \pkg{l3build} system.
%
% \subsection{Main build commands}
%
% In the working directory of a bundle or module, the following commands can be executed:
% \begin{itemize}[noitemsep]\ttfamily
% \item check
% \item check \meta{name(s)}
% \item cmdcheck
% \item clean
% \item doc
% \item install
% \item save \meta{name(s)}
% \end{itemize}
% These commands are described below.
%
% As well as these commands, the system recognises the options
% \begin{itemize}
% \item \texttt{--engine} (\texttt{-e}) Sets the engine to use for
%   testing
% \item \texttt{--halt-on-error} (\texttt{-H}) Specifies that checks
%   should stop as soon as possible, rather than running all requested
%   tests
% \item \texttt{--quiet} (\texttt{-q}) Suppresses output from unpacking
% \end{itemize}
%
% \begin{buildcmd}{check}
% The |check| command runs the entire test suite.
% This involves iterating through each \texttt{.lvt} file in the test directory (specified by the \var{testfiledir} variable), compiling each test in a \enquote{sandbox} (a directory specified by \var{testdir}), and comparing the output against each matching predefined \texttt{.tlg} file.
%
% If changes to the package or the typesetting environment have affected the results, the check for that file fails.
% A |diff| of the expected to actual output should then be inspected to determine the cause of the error; it is located in the \var{testdir} directory (default \luavar{testdir}).
%
% On Windows, the |diff| program is not available and so |fc| is used instead
% (generating an |.fc| file). Setting the environmental variables |diffexe|
% and |diffext| can be used to adjust the choice of comparison made: the standard
% values are
% \begin{itemize}
%   \item[Windows] |diffext = fc|, |diffexe = fc /n|
%   \item[*nix] |diffext = diff|, |diffexe = diff -c --strip-trailing-cr|
% \end{itemize}
%
% The following files are moved into the \enquote{sandbox} for the |check| process:
% \begin{itemize}
% \item all \var{installfiles} after unpacking;
% \item all \var{checkfiles} after unpacking;
% \item any files in the directory \var{testsuppdir};
% \item any files that match \var{checksuppfiles} in the \var{supportdir}.
% \end{itemize}
% This range of possibilities allow sensible defaults but significant flexibility for defining your own test setups.
%
% Checking can be performed with any or all of the `engines' \texttt{pdftex}, \texttt{xetex}, and \texttt{luatex}.
% By default, each test is executed with all three, being compared against the \texttt{.tlg} file produced from the \var{pdftex} engine (these defaults are controlled by the |checkengines| and |stdengine| variable respectively).
% The format used for tests can be altered by setting \var{checkformat}: the default setting \texttt{latex} means that tests are run using \emph{e.g.}~\texttt{pdflatex}, whereas setting to \texttt{plain} will run tests using \emph{e.g.}~\texttt{pdftex}.
% (Currently, this should be one of \texttt{latex} or \texttt{plain}.)
% To perform the check, the engine typesets each test \var{checkruns} times.
% More detail on this in the documentation on |save|.
% Options passed to the binary are defined in the variable \var{checkopts}.
%
% By default, |texmf| trees are searched for input files when checking. This can be disabled by setting \var{checksearch} to |false|: isolation provides confidence that the tests cannot accidentally be running with incorrect files installed in the main distribution or |hometexmf|.
% \end{buildcmd}
%
%
% \begin{buildcmd}{check \meta{name(s)}}
% Checks only the test \texttt{\meta{name(s)}.lvt}.
% All engines specified by \var{checkengines} are tested unless the command
% line option \texttt{--engine} (or \texttt{-e}) has been given to limit
% testing to a single engine.
% \end{buildcmd}
%
% \begin{buildcmd}{cmdcheck}
% For \cls{l3doc}-based sources, allows checking that the commands defined in the code part  (by \var{cmdchkfiles}) are documented in the description part.
% This is performed by passing the |check| option to the \cls{l3doc} class, typesetting the file(s) to check with engine \var{stdengine} with options \var{cmdchkopts}, and checking the resultant |.cmds| file(s).
% Dependencies are specified also with \var{checkdeps}.
% \end{buildcmd}
%
%
% \begin{buildcmd}{clean}
% This command removes all temporary files used for package bundling and regression testing.
% In the standard layout, these are all files within the directories defined by \var{localdir}, \var{testdir}, \var{typesetdir} and \var{unpackdir}, as well as all files defined in the \var{cleanfiles} variable in the same directory as the script.
% The defaults are |.pdf| files from typesetting (|doc|) and |.zip| files from bundling (|ctan|).
% \end{buildcmd}
%
%
% \begin{buildcmd}{ctan}
% Creates an archive of the package and its documentation, suitable for uploading to CTAN
% The archive is compiled in \var{distribdir}, and if the results are successful the resultant |.zip| file is moved into the same directory as the build script.
% If \var{packtdszip} is set true then  the building process includes a |.tds.zip| file containing the `\TeX\ Directory Structure' layout of the package or bundle.
% The archive therefore may contain two `views' of the package:
% \begin{Verbatim}
% abc.zip/
%         abc/
%             abc.dtx
%             abc.ins
%             abc.pdf
%             README.md
%         abc.tds.zip/
%                     doc/latex/abc/
%                                   abc.pdf
%                                   README.md
%                  source/latex/abc/
%                                   abc.dtx
%                                   abc.ins
%                     tex/latex/abc/
%                                   abc.sty
% \end{Verbatim}
% The files copied into the archive are controlled by a number of variables.
% The `root' of the TDS structure is defined by \var{tdsroot}, which is \luavar{tdsroot} by default. Plain users would redefine this to |"plain"| (or perhaps |"generic"|), for example.
% The build process for a |.tds.zip| file currently assumes a `standard'
% structure in which all extracted files should be placed inside the |tex|
% tree in a single directory, as shown above. If the module includes any
% \BibTeX{} or MakeIndex styles these will be placed in the appropriate
% subtrees.
%
% \pagebreak[2]
% The |doc| tree is constructed from:
% \begin{itemize}
% \item all files matched by \var{demofiles},
% \item all files matched by \var{docfiles},
% \item all files matched by \var{typesetfiles} with their extension replaced with |.pdf|,
% \item all files matched by \var{textfiles},
% \item all files matched by \var{bibfiles}.
% \end{itemize}
% The |source| tree is constructed from all files matched by \var{typesetfiles} and \var{sourcefiles}.
% The |tex| tree from all files matched by \var{installfiles}.
%
% Files that should always be excluded from the archive are matched against the \var{excludefiles} variable; by default this is \luavar{excludefiles}, which match Emacs' autosave files.
%
% Binary files should be specified with the \var{binaryfiles} variable (default \luavar{binaryfiles}); these are added to the zip archive without normalising line endings (text files are automatically converted to Unix-style line endings).
%
% To create the archive, by default the binary \var{zipexe} is used (\luavar{zipexe}) with options \var{zipopts} (|-v -r -X|). The intermediate build directories \var{ctandir} and \var{tdsdir} are used to construct the archive.
% \end{buildcmd}
%
%
% \begin{buildcmd}{doc}
% Compiles documentation files in the \var{typesetdir} directory.
% In the absence of one or more file names, all documentation is typeset;
% a file list may be given at the command line for selective typesetting.
% If the compilation is successful the |.pdf| is moved back into the main directory.
%
% The documentation compilation is performed with the \var{typesetexe} binary (default \texttt{pdflatex}), with options \var{typesetopts}.
% Additional \TeX{} material defined in \var{typesetcmds} is passed to the document (e.g., for writing |\\PassOptionsToClass{l3doc}{letterpaper}|, and so on---note that backslashes need to be escaped in Lua strings).
%
% Files that match |typesetsuppfiles| in the |support| directory (|supportdir|) are copied into the |build/local| directory (|localdir|) for the typesetting compilation process.
% Additional dependencies listed in the \var{typesetdeps} variable (empty by default) will also be installed.
%
% If \var{typesetsearch} is \code{true} (default), standard \texttt{texmf} search trees are used in the typesetting compilation. If set to false, \emph{all} necessary files for compilation must be included in the |build/local| sandbox.
% \end{buildcmd}
%
%
% \begin{buildcmd}{install}
% Copies all package files (defined by \var{installfiles}) into the user's home \texttt{texmf} tree in the form of the \TeX\ Directory Structure.
% \end{buildcmd}
%
%
% \begin{buildcmd}{save \meta{name(s)}}
% This command runs through the same execution as |check| for a specific test(s) \texttt{\meta{name(s)}.lvt}.
% This command saves the output of the test to a |.tlg| file.
% This file is then used in all subsequent checks against the \texttt{\meta{name}.lvt} test.
%
% If the \texttt{--engine} (or \texttt{-e}) is specified (one of |pdftex|, |xetex|, or |luatex|), the saved output is stored in \texttt{\meta{name}.\meta{engine}.tlg}. This is necessary if running the test through a different engine produces a different output.
% A normalisation process is performed when checking to avoid common differences such as register allocation; full details are listed in section~\ref{sec:norm}.
% \end{buildcmd}
%
%
% \begin{buildcmd}{unpack}
% This is an internal target that is normally not needed on user level.
% It unpacks all files into the directory defined by \var{unpackdir}. This occurs before other build commands such as |doc|, |check|, etc.
%
% The unpacking process is performed by executing the \var{unpackexe} (default \texttt{tex}) with options \var{unpackopts} on all files defined by the \var{unpackfiles} variable; by default, all files that match \luavar{unpackfiles}.
%
% If additional support files are required for the unpacking process, these can be enumerated in the \var{unpacksuppfiles} variable.
% Dependencies for unpacking are defined with \var{unpackdeps}.
%
% By default this process allows files to be accessed in all standard |texmf| trees; this can be disabled by setting \var{unpacksearch} to |false|.
% \end{buildcmd}
%
% \subsection{Example build scripts}
%
% An example of a standalone build script for a package that uses self-contained |.dtx| files is shown in Figure~\ref{fig:breqn}.
% Here, the |module| only is defined, and since it doesn't use |.ins| files so the variable \var{unpackfiles} is redefined to run |tex| on the |.dtx| files instead to generate the necessary |.sty| files.
% There are some PDFs in the repository that shouldn't be part of a CTAN submission, so they're explicitly excluded, and here unpacking is done `quietly' to minimise console output when building the package.
% Finally, because this is a standalone package, we assume that \pkg{l3build} is installed in the main \TeX{} distribution and find the Lua script by searching for it.
%
% \begin{figure}[!b]
%   \begin{lstlisting}[frame=single,language={[5.2]Lua},gobble = 6]
%     #!/usr/bin/env texlua
%
%     -- Build script for breqn
%
%     module = "breqn"
%
%     unpackfiles = {"*.dtx"}
%     excludefiles = {"*/breqn-abbr-test.pdf",
%                     "*/eqbreaks.pdf"}
%     unpackopts  = "-interaction=batchmode"
%
%     kpse.set_program_name("kpsewhich")
%     dofile(kpse.lookup("l3build.lua"))
%   \end{lstlisting}
% \caption{The build script for the \pkg{breqn} package.}
% \label{fig:breqn}
% \end{figure}
%
% An example of a bundle build script for \pkg{l3packages} is shown in Figure~\ref{fig:bundle}.
% Note for \LaTeX3 we use a common file to set all build variables in one place, and the path to the |l3build.lua| script is hard-coded so we always use our own most recent version of the script.
% An example of an accompanying module build script is shown in Figure~\ref{fig:module}.
%
% \begin{figure}[p]
%   \begin{lstlisting}[frame=single,language={[5.2]Lua},gobble = 6]
%     #!/usr/bin/env texlua
%
%     -- Build script for LaTeX3 "l3packages" files
%
%     -- Identify the bundle: there is no module as this is the "driver"
%     bundle = "l3packages"
%
%     -- Location of main directory: use Unix-style path separators
%     maindir = ".."
%
%     -- Load the common build code: this is the one place that a path
%     -- needs to be hard-coded
%     dofile (maindir .. "/l3build/l3build-config.lua")
%     dofile (maindir .. "/l3build/l3build.lua")
%   \end{lstlisting}
% \caption{The build script for the \pkg{l3packages} bundle.}
% \label{fig:bundle}
% \end{figure}
%
% \begin{figure}[p]
%   \begin{lstlisting}[frame=single,language={[5.2]Lua},gobble = 6]
%     #!/usr/bin/env texlua
%
%     -- Build script for LaTeX3 "xparse" files
%
%     -- Identify the bundle and module:
%     bundle = "l3packages"
%     module = "xparse"
%
%     -- Location of main directory: use Unix-style path separators
%     -- Should match that defined by the bundle.
%     maindir = "../.."
%
%     -- Load the common build code: this is the one place that a path
%     -- needs to be hard-coded
%     dofile (maindir .. "/l3build/l3build-config.lua")
%     dofile (maindir .. "/l3build/l3build.lua")
%   \end{lstlisting}
% \caption{The build script for the \pkg{xparse} module.}
% \label{fig:module}
% \end{figure}
%
% \begin{figure}[p]
%   \begin{lstlisting}[frame=single,gobble = 6]
%     @echo off
%     texlua build.lua %*
%   \end{lstlisting}
% \caption{Windows batch file wrapper for running the build process.}
% \label{fig:batch}
% \end{figure}
%
% Under a Unix-like platform, you may wish to run `|chmod +x build.lua|' on these files, which allows a simpler command line use. Instead of writing\\
% \hspace*{2\parindent}|texlua build.lua check|\\ for example, you would simply write\\
% \hspace*{2\parindent}|./build.lua check|\\
% instead. (Or even omit the |./| depending on your path settings.)
% Windows users can achieve a similar effect by creating a file |build.bat| as show in Figure~\ref{fig:batch}.
%
% \subsection{Variables}
%
% This section lists all variables defined in the |l3build.lua| script that are available for customisation.
%
% \luavartypeset
%
% \subsection{Dependencies}
%
% If you have multiple packages that are developed separately but still interact in some way, it's often desirable to integrate them when performing regression tests.
% For \LaTeX3, for example, when we make changes to \pkg{l3kernel} it's important to check that the tests for \pkg{l3packages} still run correctly, so it's necessary to include the \pkg{l3kernel} files in the build process for \pkg{l3packages}.
%
% In other words, \pkg{l3packages} is \emph{dependent} on \pkg{l3kernel}, and this is specified in \pkg{l3build} by setting appropriately the variables \texttt{checkdeps}, \texttt{typesetdeps}, and \texttt{unpackdeps}.
% The relevant parts of the \LaTeX3 repository is structured as the following.
% \Needspace{3\baselineskip}
% \begin{Verbatim}
% l3/
%    l3kernel/
%               build.lua
%               expl3.dtx
%               expl3.ins
%               ...
%               testfiles/
%    l3packages/
%               build.lua
%               xparse/
%                      build.lua
%                      testfiles/
%                      xparse.dtx
%                      xparse.ins
%    support/
% \end{Verbatim}
% For \LaTeX3 build files, |maindir| is defined as top level folder |l3|, so all support files are located here, and the build directories will be created there.
% To set \pkg{l3kernel} as a dependency of \pkg{l3package}, within |l3packages/xparse/build.lua| the equivalent of the following is set:
% \begin{Verbatim}
%   maindir = "../.."
%   checkdeps = {maindir .. "/l3kernel"}
% \end{Verbatim}
% This ensures that the \pkg{l3kernel} code is included in all processes involved in unpacking and checking and so on.
% The name of the script file in the dependency is set with the |scriptname| variable; by default these are |"build.lua"|.
%
%
% \subsection{Output normalisation}
% \label{sec:norm}
%
% To allow test files to be used between different systems (\emph{e.g.}~when
% multiple developers are involved in a project), the log files are normalised
% before comparison during checking. This removes some system-dependent
% data but also some variations due to different engines. This normalisation
% consists of two parts: removing (\enquote{ignoring}) some lines and modifying
% others to give consistent test. Currently, the following types of line are
% ignored:
% \begin{itemize}
%   \item Lines before the \cs{START}, after the \cs{END} and within
%     \cs{OMIT}/\cs{TIMO} blocks
%   \item Entirely blank lines, including those consisting only of spaces.
%   \item Lines containing file dates in format
%    \texttt{\meta{yyyy}/\meta{mm}/\meta{dd}}.
%  \item Lines starting \cs{openin} or \cs{openout}.
% \end{itemize}
% Modifications made in lines are:
% \begin{itemize}
%   \item Removal of the name of the test file itself.
%   \item Removal of the |pdftex.map| load information given during
%     first page shipout.
%   \item Removal spaces at the start of lines.
%   \item Removal of |./| at start of file names.
%   \item Standardisation of the list of units known to \TeX{} (\pdfTeX{}
%     and \LuaTeX{} add a small number of additional units which are not
%     known to \TeX90 or \XeTeX{}).
%   \item Standardisation of \verb*|\csname\endcsname | to |\csname\endcsname|
%     (the former is formally correct, but the latter was produced for many
%     years due to a \TeX{} bug).
%   \item Conversion of \texttt{on line \meta{number}} to \texttt{on line ...}
%     to allow flexibility in changes to test files.
%   \item
% \end{itemize}
%
% \LuaTeX{} makes several additional changes to the log file. As normalising
% these may not be desirable in all cases, they are handled separately.
% When creating \LuaTeX{}-specific test files (either with \LuaTeX{} as
% the standard engine or saving a \LuaTeX{}-specific |.tlg| file) no further
% normalisation is undertaken. On the other hand, for cross-engine comparison
% the following normalisation is applied:
% \begin{itemize}
%   \item Removal of additional (unused) |\discretionary| points.
%   \item Removal of |U+...| notation for missing characters.
%   \item Removal of |display| for display math boxes
%     (included by \TeX90/\pdfTeX{}/\XeTeX).
%   \item Removal of Omega-like |direction TLT| information.
%   \item Removal of additional whatsit containing local paragraph information
%     (|\localinterlinepenalty|, \emph{etc.}).
%   \item Rounding of glue set to four decimal places (glue set may be
%     slightly different in \LuaTeX{} compared to other engines).
%   \item Conversion of low chars ($1$ to $31$) to |^^| notation.
% \end{itemize}
%
% When making comparisons between 8-bit and Unicode engines it is useful to
% format the top half of the 8-bit range such that it appears in the log as
% |^^|\texttt{\meta{char}} (the exact nature of the 8-bit output is otherwise
% dependent on the active code page). This may be controlled using the
% |asciiengines| option. Any engines named here will use a |.tcx| file to
% produce only ASCII chars in the log output, whilst for other engines
% normalisation is carried out from UTF-8 to ASCII. If the option is set to
% an empty table the latter process is skipped: suitable for cases where only
% Unicode engines are in use.
%
% \section{Writing test files}
% \label{sec:writing-tests}
%
% Test files are written in a \TeX{} dialect using the support file |regression-test.tex|, which should be |\input| at the very beginning of each test.
% Additional customisations to this driver can be included in a local |regression-test.cfg| file, which will be loaded automatically if found.
%
% The macros loaded by |regression-test.tex| set up the test system and provide a number of commands to aid the production of a structured test suite.
% The basis of the test suite is to output material into the |.log| file, from which a normalised test output (|.tlg|) file is produced by the build command |save|.
% A number of commands are provided for this; they are all written in uppercase to help avoid possible conflicts with other package commands.
%
% \subsection{Metadata and structural commands}
%
% Any commands that write content to the |.log| file that should be ignored can be surrounded by |\OMIT| \dots\ |\TIMO|.
% At the appropriate location in the document where the |.log| comparisons should start (say, after |\begin{document}|), the test suite must contain the |\START| macro.
% The test should then include \cs{AUTHOR}\marg{authors details} in case a test file fails in the future and needs to be re-analysed.
%
% Some additional diagnostic information can then be included as metadata for the conditions of the test.
% The desired format can be indicated with \cs{FORMAT}\marg{format name}, and any packages or classes loaded can be indicated with
%
% \noindent\hspace*{2\parindent} \cs{CLASS}\oarg{options}\marg{class name, version}\par
% \noindent\hspace*{2\parindent} \cs{PACKAGE}\oarg{options}\marg{package name, version}
%
% \noindent These do not provide information that is useful for automated checking; after all, packages change their version numbers frequently.
% Rather, including this information in a test indicates the conditions under which the test was definitely known to pass at a certain time in the past.
%
% The |\END| command signals the end of the test (but read on).
% Some additional diagnostic information is printed at this time to debug if the test did not complete `properly' in terms of mismatched brace groups or \cs{if}\dots\cs{fi} groups.
%
% In a \LaTeX{} document, |\end{document}| will implicitly call |\END| at the very end of the  compilation process.
% If |\END| is used directly (replacing |\end{document}| in the test), the compilation will halt almost immediately, and various tasks that |\end{document}| usually performs will not occur (such as potentially writing to the various |.toc| files, and so on). This can be an advantage if there is additional material printed to the log file in this stage that you wish to ignore, but it is a disadvantage if the test relies on various auxiliary data for a subsequent typesetting run.
% (See the \var{checkruns} variable for how these tests would be test up.)
%
% \subsection{Commands to help write tests}
%
% A simple command \cs{CHECKCOMMAND}\cs{\meta{macro}} is provided to check whether a particular \cs{\meta{macro}} is defined, undefined, or equivalent to \cs{relax}.
% This is useful to flag either that internal macros are remaining local to their definitions, or that defined commands definitely are defined, or even as a reminder that commands you intend to define in a future package need to be tested once they appear.
%
% \cs{TYPE} is used to write material to the \texttt{.log} file, like \LaTeX's \cs{typeout}, but it allows `long' input.
% The following commands are defined to use \cs{TYPE} to output strings to the \texttt{.log} file.
% \begin{itemize}
% \item
% \cs{SEPARATOR} inserts a long line of \texttt{=} symbols to break up the log output.
% \item
% \cs{NEWLINE} inserts a linebreak into the log file.
% \item
% \cs{TRUE}, \cs{FALSE}, \cs{YES}, \cs{NO} output those strings to the log file.
% \item
% \cs{ERROR} is \emph{not} defined but is commonly used to indicate a code path that should never be reached.
% \item
% The \cs{TEST}\marg{title}\marg{contents} command surrounds its \meta{contents} with some \cs{SEPARATOR}s and a \meta{title}.
% \item
% \cs{TESTEXP} surrounds its contents with \cs{TYPE} and formatting to match \cs{TEST}; this can be used as a shorthand to test expandable commands.
% \item
% TODO: would a \cs{TESTFEXP} command (based on \cs{romannumeral} expansion) be useful as well?
% \end{itemize}
% An example of some of these commands is shown following.
% \begin{Verbatim}
% \TEST{bool_set,~lazy~evaluation}
%  {
%   \bool_set:Nn \l_tmpa_bool
%    {
%     \int_compare_p:nNn 1=1
%     && \bool_if_p:n
%      {
%       \int_compare_p:nNn 2=3 ||
%       \int_compare_p:nNn 4=4 ||
%       \int_compare_p:nNn 1=\ERROR % is skipped
%      }
%     && \int_compare_p:nNn 2=2
%    }
%   \bool_if:NTF \l_tmpa_bool \TRUE \FALSE
%  }
% \end{Verbatim}
% This test will produce the following in the output.
% \begin{Verbatim}
% ==========================================
% TEST 8: bool_set, lazy evaluation
% ==========================================
% TRUE
% ==========================================
% \end{Verbatim}
% (Only if it's the eighth test in the file of course, and assuming \pkg{expl3}
% coding conventions are active.)
%
% \subsection{Showing box content}
%
% The commands introduced above are only useful for checking algorithmic or logical correctness.
% Many packages should be tested based on their typeset output instead; \TeX{} provides a mechanism for this by printing the contents of a box to the log file.
% The |regression-test.tex| driver file sets up the relevant \TeX{} parameters to produce as much output as possible when showing box output.
%
% A plain \TeX{} example of showing box content follows.
% \begin{Verbatim}[frame=single,fontsize=\small]
% \input regression-test.tex\relax
% \START
% \setbox0=\hbox{\rm hello \it world $a=b+c$}
% \showbox0
% \END
% \end{Verbatim}
% This produces the output shown in Figure~\ref{fig:box-log} (left side).
% It is clear that if the definitions used to typeset the material in the box changes, the log output will differ and the test will no longer pass.
%
% The equivalent test in \LaTeXe{} using \pkg{expl3} is similar.
% \begin{Verbatim}[frame=single,fontsize=\small]
% \input{regression-test.tex}
% \documentclass{article}
% \usepackage{expl3}
% \START
% \ExplSyntaxOn
% \box_new:N \l_tmp_box
% \hbox_set:Nn \l_tmp_box {hello~ \emph{world}~ $a=b+c$}
% \box_show:N \l_tmp_box
% \ExplSyntaxOff
% \END
% \end{Verbatim}
% The output from this test is shown in Figure~\ref{fig:box-log} (right side).
% There is marginal difference (mostly related to font selection and different logging settings in \LaTeX) between the plain and \pkg{expl3} versions.
%
% When examples are not self-contained enough to be typeset into boxes, it is possible to ask \TeX{} to output the entire contents of a page.
% Insert \cs{showoutput} for \LaTeX{} or set \cs{tracingoutput} positive for plain \TeX{}; ensure that the test ends with \cs{newpage} or equivalent because \TeX{} waits until the entire page is finished before outputting it.
%
% TODO: should we add something like \cs{TRACEPAGES} to be format-agnostic here? Should this perhaps even be active by default?
%
% \begin{figure}
% \hspace*{-3cm}
%   \begin{BVerbatim}[fontsize=\small]
% > \box0=
% \hbox(6.94444+0.83333)x90.56589
% .\tenrm h
% .\tenrm e
% .\tenrm l
% .\tenrm l
% .\tenrm o
% .\glue 3.33333 plus 1.66666 minus 1.11111
% .\tenit w
% .\tenit o
% .\tenit r
% .\tenit l
% .\tenit d
%
% .\glue 3.57774 plus 1.53333 minus 1.0222
% .\mathon
% .\teni a
% .\glue(\thickmuskip) 2.77771 plus 2.77771
% .\tenrm =
% .\glue(\thickmuskip) 2.77771 plus 2.77771
% .\teni b
% .\glue(\medmuskip) 2.22217 plus 1.11108 minus 2.22217
% .\tenrm +
% .\glue(\medmuskip) 2.22217 plus 1.11108 minus 2.22217
% .\teni c
% .\mathoff
%
% ! OK.
% l.9 \showbox0
%
%
%   \end{BVerbatim}
%   \qquad
%   \begin{BVerbatim}[fontsize=\small]
% > \box71=
% \hbox(6.94444+0.83333)x91.35481
% .\OT1/cmr/m/n/10 h
% .\OT1/cmr/m/n/10 e
% .\OT1/cmr/m/n/10 l
% .\OT1/cmr/m/n/10 l
% .\OT1/cmr/m/n/10 o
% .\glue 3.33333 plus 1.66666 minus 1.11111
% .\OT1/cmr/m/it/10 w
% .\OT1/cmr/m/it/10 o
% .\OT1/cmr/m/it/10 r
% .\OT1/cmr/m/it/10 l
% .\OT1/cmr/m/it/10 d
% .\kern 1.03334
% .\glue 3.33333 plus 1.66666 minus 1.11111
% .\mathon
% .\OML/cmm/m/it/10 a
% .\glue(\thickmuskip) 2.77771 plus 2.77771
% .\OT1/cmr/m/n/10 =
% .\glue(\thickmuskip) 2.77771 plus 2.77771
% .\OML/cmm/m/it/10 b
% .\glue(\medmuskip) 2.22217 plus 1.11108 minus 2.22217
% .\OT1/cmr/m/n/10 +
% .\glue(\medmuskip) 2.22217 plus 1.11108 minus 2.22217
% .\OML/cmm/m/it/10 c
% .\mathoff
%
% ! OK.
% <argument> \l_tmp_box
%
% l.12 \box_show:N \l_tmp_box
%   \end{BVerbatim}
%   \caption{Output from displaying the contents of a simple box to the log file, using plain \TeX{} (left) and \pkg{expl3} (right). Some blank lines have been added to the plain \TeX{} version to help with the comparison.}
%   \label{fig:box-log}
% \end{figure}
%
% \section{Alternative test formats}
%
% \subsection{Generating test files with \pkg{DocStrip}}
%
% It is  possible to pack tests inside source files. Tests generated during the
% unpacking process will be available to the \texttt{check} and \texttt{save}
% commands as if they were stored in the \texttt{testfiledir}. Any explicit
% test files inside \texttt{testfiledir} take priority over generated ones
% with the same names.
%
% \subsection{Specifying expectations}
%
% Regression tests check whether changes introduced in the code modify the test
% output. Especially while developing a complex package there is not yet a
% baseline to save a test goal with. It might then be easier to formulate the
% expected effects and outputs of tests directly. To achieve this, you may
% create an \texttt{.lve} instead of a \texttt{.tlg}
% file.\footnote{Mnemonic: \texttt{lv\textbf{t}}: \textbf{t}est,
% \texttt{lv\textbf{e}}: \textbf{e}xpectation} It is processed exactly like
% the \texttt{.lvt} to generate the expected outcome. The test fails when both
% differ.
%
% Combining both features enables contrasting the test with its expected
% outcome in a compact format. Listing \ref{fig:expect-dtx} exemplary tests
% \TeX{}s counters. Listing \ref{fig:expect-ins} shows the relevant part of an
% \texttt{.ins} file to generate it.
%
% \begin{figure}
%   \begin{lstlisting}[frame=single,language={TeX},gobble = 6]
%     \input regression-test.tex\relax
%     \START
%     \TEST{counter-math}{
%     %<*test>
%       \OMIT
%       \newcounter{numbers}
%       \setcounter{numbers}{2}
%       \addtocounter{numbers}{2}
%       \stepcounter{numbers}
%       \TIMO
%       \typeout{\arabic{numbers}}
%     %</test>
%     %<expect>  \typeout{5}
%     }
%     \END
%   \end{lstlisting}
%   \caption{Test and expectation can be specified side-by-side in a single
%     \texttt{.dtx} file.}
%   \label{fig:expect-dtx}
% \end{figure}
%
%\begin{figure}
%   \begin{lstlisting}[frame=single,language={TeX},gobble = 6]
%      \generate{\file{\jobname.lvt}{\from{\jobname.dtx}{test}}
%                \file{\jobname.lve}{\from{\jobname.dtx}{expect}}}
%   \end{lstlisting}
%   \caption{Test and expectation are generated from a \texttt{.dtx} file of
%     the same name.}
%   \label{fig:expect-ins}
% \end{figure}
%
% \subsection{Typesetting documentation}
%
% As part of the overall build process, \pkg{l3build} will create PDF
% documentation as described earlier. The standard build process for PDFs
% will attempt to run Biber, \BibTeX{} and MakeIndex as appropriate
% (the exact binaries used are defined by \luavar{biberexe}, \luavar{bibtexexe}
% and \luavar{makeindexexe}). However, there is no attempt to create an entire
% PDF creation system in the style of \texttt{latexmk} or similar.
%
% For package authors who have more complex requirements than those covered
% by the standard set up, the Lua script offers the possibility for
% customisation. The Lua function \texttt{typeset} may be defined before
% reading \texttt{l3build.lua} and should take one argument, the name of
% the file to be typeset. Within this function, the auxiliary Lua
% functions \texttt{biber}, \texttt{bibtex}, \texttt{makeindex} and
% \texttt{tex} can be used, along with custom code, to define a PDF
% typesetting pathway. The functions \texttt{biber} and \texttt{bibtex}
% take a single argument: the name of the file to work with \emph{minus}
% any extension. The \texttt{tex} takes as an arugment the full name
% of the file. The most complex function \texttt{makeindex} requires the
% name, input extension, putput extension, log extension and style name.
% For example,  Figure~\ref{fig:PDF} shows a simple script which might
% apply to a case where multiple \BibTeX{} runs are needed (perhaps where
% citations can appear within other references).
%
% \begin{figure}[!b]
%   \begin{lstlisting}[frame=single,language={[5.2]Lua},gobble = 6]
%     #!/usr/bin/env texlua
%
%     -- Build script with custom PDF route
%
%     module = "mymodule"
%
%     function typeset (file)
%       local name = string.match (file, "^(.*)%.") or name
%       local errorlevel = tex (file)
%       if errorlevel == 0 then
%         -- Return a non-zero errorlevel if anything goes wrong
%         errorlevel = (
%           bibtex (name) +
%           tex (file)    +
%           bibtex (name) +
%           tex (file)    +
%           tex (file)
%         )
%       end
%       return errorlevel
%     end
%
%     kpse.set_program_name("kpsewhich")
%     dofile(kpse.lookup("l3build.lua"))
%   \end{lstlisting}
%   \caption{A customised PDF creation script.}
%   \label{fig:PDF}
% \end{figure}
%
% \end{documentation}
%
% \begin{implementation}
%
% \clearpage
% \section{\texttt{regression-test.tex}}
%
% This section describes the code for setting up the regression test system.
% Each test file should start with |\input regression-test.tex\relax|.
%
%    \begin{macrocode}
%<*package>
%    \end{macrocode}
%
% \subsection{Preliminaries}
%
% Unlike in the \LaTeXe{} regression test suite, reset catcodes: each test should set these
% as appropriate.
%    \begin{macrocode}
\expandafter\edef\csname reset\string @catcodes\endcsname{%
  \catcode`\noexpand\@=\the\catcode`\@\relax
}
\catcode`\@=11 %
%    \end{macrocode}
% Put \TeX{} into scroll mode, and stop it showing the
% implementation details of macros in error messages.
%    \begin{macrocode}
\scrollmode
\errorcontextlines=-1 %
%    \end{macrocode}
%
% Show all box details: this avoids getting variable results if boxes
% have different numbers of lines (\LuaTeX{} adds extra information).
%    \begin{macrocode}
\showboxbreadth=\maxdimen
\showboxdepth=\maxdimen
%    \end{macrocode}
%
% The |\showoutput| command of \LaTeX{} calls |\loggingoutput| which in
% turn calls |\errorstopmode| but we want to continue running without
% any stops.
%    \begin{macrocode}
\def\loggingoutput{\tracingoutput1
    \showboxbreadth\maxdimen\showboxdepth\maxdimen}
%    \end{macrocode}

%
% Set the newline character: \LaTeXe{} does this but plain-based formats
% do not.
%    \begin{macrocode}
\newlinechar=`\^^J
%    \end{macrocode}
%
% \subsection{Commands in test files}
%
% A long version of |\typeout|, because tests may contain |\par| tokens.
% Besides, with that |\TYPE|, we can do |\TYPE { ... \TRUE ... \NEWLINE ... }|.
%    \begin{macrocode}
\long\def\LONGTYPEOUT#1{%
  \begingroup
    \long\def\TYPE##1{##1}%
    \immediate\write17{#1}%
  \endgroup
}
\let\TYPE\LONGTYPEOUT
%    \end{macrocode}
%
% Start the test, after the optional |\documentclass|
% |\begin{document}| commands with |\START|.  All lines in the |.log| file
% before this will be ignored.
%
% It also prints a DocStrip-style
% character table in the |.tlg| file.
% Is this necessary any more? Probably too late to remove it.
%    \begin{macrocode}
\def\STARTMESSAGE{This is a generated file for the l3build validation system.}
\def\START{\LONGTYPEOUT{START-TEST-LOG^^J^^J%
   \STARTMESSAGE%
^^J^^JDon't change this file in any respect.%
^^J^^J\CTable^^J}}
\begingroup
\catcode`\^^\=0
\catcode`\^^A=\catcode`\%
^^\catcode`^^\ =11
^^\catcode`^^\%=11
^^\catcode`^^\#=11
^^\catcode`^^\~=11
^^\endlinechar=`^^\^^J
^^\catcode`^^\\=11^^A
^^\gdef^^\CTable{
%% \CharacterTable
%%  {Upper-case    \A\B\C\D\E\F\G\H\I\J\K\L\M\N\O\P\Q\R\S\T\U\V\W\X\Y\Z
%%   Lower-case    \a\b\c\d\e\f\g\h\i\j\k\l\m\n\o\p\q\r\s\t\u\v\w\x\y\z
%%   Digits        \0\1\2\3\4\5\6\7\8\9
%%   Exclamation   \!     Double quote  \"     Hash (number) \#
%%   Dollar        \$     Percent       \%     Ampersand     \&
%%   Acute accent  \'     Left paren    \(     Right paren   \)
%%   Asterisk      \*     Plus          \+     Comma         \,
%%   Minus         \-     Point         \.     Solidus       \/
%%   Colon         \:     Semicolon     \;     Less than     \<
%%   Equals        \=     Greater than  \>     Question mark \?
%%   Commercial at \@     Left bracket  \[     Backslash     \\
%%   Right bracket \]     Circumflex    \^     Underscore    \_
%%   Grave accent  \`     Left brace    \{     Vertical bar  \|
%%   Right brace   \}     Tilde         \~}
%%
}^^A
^^\endgroup{}%
%    \end{macrocode}
% The test should end with |\END| or |\end{document}|
%    \begin{macrocode}
\ifx\@@end\@undefined
  \let\@@@end\end
\else
  \let\@@@end\@@end
\fi
\def\END
  {%
    \ifx\currentiflevel\@undefined\else
      \ifnum\currentgrouplevel>0 %
        \LONGTYPEOUT{Bad grouping: \the\currentgrouplevel!}%
      \fi
      \ifnum\currentiflevel>2 %
        \LONGTYPEOUT{Bad conditionals: \the\numexpr\currentiflevel-2!}%
      \fi
    \fi
    \LONGTYPEOUT{END-TEST-LOG}\@@@end
  }
\let\@@end\END
%    \end{macrocode}
% After the |\START| should come declarations of the format and style
% options being used.
%    \begin{macrocode}
\def\FORMAT#1{\LONGTYPEOUT{Format: #1}%
  \def\@tempa{#1}\ifx\@tempa\@EJ\else
   \OMIT\TYPE{WARNING: Declared format #1,^^JActual format \@EJ}\TIMO\fi}
%    \end{macrocode}
% The old version got this information from everyjob,
% but that does not work with \LaTeXe\ as |\everyjob| is cleared.
%    \begin{macrocode}
\edef\@EJ{\fmtname <\fmtversion>}
%    \end{macrocode}
% Some author info:
%    \begin{macrocode}
\def\AUTHOR#1{\LONGTYPEOUT{Author: #1}}
%    \end{macrocode}
% Surround commands which produce irrelevant lines in the .log file by
% |\OMIT|\dots|\TIMO|
%    \begin{macrocode}
\def\OMIT{\LONGTYPEOUT{OMIT}}
\def\TIMO{\LONGTYPEOUT{TIMO}}
%    \end{macrocode}
% Not all packages declare themselves to the log file, and we can not
% rely on TeX`s output as it includes full path names, and does not
% include version numbers etc.
%
% If the class or package is loaded with options, you may
% specify the options in the |\CLASS| (|\PACKAGE|) declaration. eg:
% \begin{verbatim}
% \CLASS[german,a4page]{article v2.0 1994/01/02}
% \PACKAGE{ifthen v2.2 1993/11/12}
% \PACKAGE[dvips]{graphics v 3.8 1994/02/02}
% \end{verbatim}
%    \begin{macrocode}
\def\CLASS{\@ifnextchar[\OPTCLASS\XCLASS}
\def\OPTCLASS[#1]#2{%
  \TYPE{Main Class: #2^^J\space\space\space\space Options: #1}}
\def\XCLASS#1{%
  \TYPE{Main Class: #1}}
\def\PACKAGE{\@ifnextchar[\OPTPACKAGE\XPACKAGE}
\def\OPTPACKAGE[#1]#2{%
  \TYPE{Package: #2^^J\space\space\space\space Options: #1}}
\def\XPACKAGE#1{%
  \TYPE{Package: #1}}
%    \end{macrocode}
%
% The commands above require 2e's \verb|\@ifnextchar|, so copy that definition verbatim if necessary:
%    \begin{macrocode}
\ifx\@ifnextchar\@undefined
\long\def\@ifnextchar#1#2#3{%
  \let\reserved@d=#1%
  \def\reserved@a{#2}%
  \def\reserved@b{#3}%
  \futurelet\@let@token\@ifnch}
\def\@ifnch{%
  \ifx\@let@token\@sptoken
    \let\reserved@c\@xifnch
  \else
    \ifx\@let@token\reserved@d
      \let\reserved@c\reserved@a
    \else
      \let\reserved@c\reserved@b
    \fi
  \fi
  \reserved@c}
\def\:{\let\@sptoken= } \: % this makes \@sptoken a space token
\def\:{\@xifnch} \expandafter\def\: {\futurelet\@let@token\@ifnch}
\fi
%    \end{macrocode}
% After the above declarations, and before the main tests, you may
% optionally declare' all the commands in the `module' that you are
% about to test. These commands will be registered as defined,
% undefined or relaxed (i.e.~|\let| to |\relax|). You may wish to declare
% commands not currently implemented, so that if they are added at a
% later stage, the test will fail, reminding someone to document the
% fact that the user interface has changed.
%    \begin{macrocode}
\def\CHECKCOMMAND#1{%
  \ifx#1\@undefined\LONGTYPEOUT{Undefined \string#1}\else
  \ifx#1\relax\LONGTYPEOUT{Relaxed \space\space\string#1}\else
         \LONGTYPEOUT{Defined \space\space\string#1}\fi\fi}
%    \end{macrocode}
% To allow testing of possible changes, we allow extra code to be read
% in before the test starts. The necessary code should be placed in a
% file |regression-test.cfg|.
%    \begin{macrocode}
\OMIT
\ifx\InputIfFileExists\@undefined
\newread\@inputcheck
\long\def\InputIfFileExists#1#2#3{%
  \openin\@inputcheck#1\relax
  \ifeof\@inputcheck
    \def\reserved@a{#3}%
  \else
    \def\reserved@a{#2\input #1\relax}%
  \fi
  \closein\@inputcheck
  \reserved@a}
\fi
\InputIfFileExists{regression-test.cfg}
      {\LONGTYPEOUT{^^J***^^Jregression-test.cfg in operation^^J***^^J}}{}
\TIMO
%    \end{macrocode}
%
% \subsection{Formatting the \texttt{.log} file}
%
% We are not starved for space in the log file output, so let's make it as
% verbose as is useful when reading the |.diff|'s.
%    \begin{macrocode}
\newcount \gTESTint
\def\SEPARATOR{%
  \TYPE{%
    ============================================================%
  }%
}
%    \end{macrocode}
%    \begin{macrocode}
\long\def\TEST#1#2{%
  \advance \gTESTint 1 %
  \SEPARATOR
  \LONGTYPEOUT{%
    TEST \the\gTESTint: \detokenize{#1}}%
  \SEPARATOR
  \begingroup
    \let\TYPE\LONGTYPEOUT
    #2%
  \endgroup
  \SEPARATOR \LONGTYPEOUT{}%
}
\long\def\TESTEXP#1#2{%
  \advance \gTESTint 1 %
  \SEPARATOR
  \LONGTYPEOUT{%
    TEST \the\gTESTint: \detokenize{#1}}%
  \SEPARATOR
  \begingroup
    \long\def\TYPE##1{##1}%
    \LONGTYPEOUT{#2}%
  \endgroup
  \SEPARATOR
  \LONGTYPEOUT{}%
}

\def \TRUE  {\TYPE{TRUE}}
\def \FALSE {\TYPE{FALSE}}
\def \YES   {\TYPE{YES}}
\def \NO    {\TYPE{NO}}

\def \NEWLINE {\TYPE{^^J}}
%    \end{macrocode}
% Finish up.
%    \begin{macrocode}
\reset@catcodes
%    \end{macrocode}
%
%    \begin{macrocode}
%</package>
%    \end{macrocode}
%
% \newpage
% \section{\texttt{l3build.lua}}
%
% This section consists of the |l3build.lua| code.
% This code is \emph{not} generated from |l3build.dtx| since it needs to already be extracted to build \pkg{l3build} itself!
% As Frank says, we don't want to end up with a double M\"unchhausen.
%
% \lstinputlisting
%   [
%    basicstyle=\ttfamily\scriptsize,
%    numbers=left,
%    numberstyle={\tiny\color[gray]{0.4}},
%    language={[5.2]Lua},
%    procnamekeys=function,
%    procnamestyle=\color{red},
%   ]
%   {l3build.lua}
%
% \end{implementation}
%
% \PrintIndex