forest (9apr16)

git-svn-id: svn://tug.org/texlive/trunk@40367 c570f23f-e606-0410-a88d-b1316a301751

3 files changed, 391 insertions, 139 deletions

diff --git a/Master/texmf-dist/tex/latex/forest/forest-compat.sty b/Master/texmf-dist/tex/latex/forest/forest-compat.sty
index 8921cf5405a..4245f103044 100644
--- a/Master/texmf-dist/tex/latex/forest/forest-compat.sty
+++ b/Master/texmf-dist/tex/latex/forest/forest-compat.sty
@@ -31,20 +31,24 @@
 \forestset{@@deprecated/.code={\forest@deprecated{#1}}}
 \def\forestcompat#1{\pgfqkeys{/forest/@compat}{#1}}
 \forestcompat{
+  silent/.style={\def\forest@deprecated##1{}},
+  %%% begin listing region: compat_keys
   most/.style={1.0-most},
   all/.style={1.0-all},
   none/.style={},
-  silent/.style={\def\forest@deprecated##1{}},
-  %%% begin listing region: compat_1.0
   1.0-most/.style={
     1.0-triangle,1.0-linear,1.0-nodewalk,1.0-ancestors,
     1.0-fittotree,1.0-for,1.0-forall
   },
   1.0-all/.style={
     1.0-most,
-    1.0-ignoreinvalidsteps,1.0-rotate,1.0-stages,1.0-name
+    1.0-forstep,1.0-rotate,1.0-stages,1.0-name,
+    2.0.2-all,
   },
-  %%% end listing region: compat_1.0
+  2.0.2-all/.style={
+    2.0.2-delayn,2.0.2-wrapnpgfmathargs,
+  },
+  %%% end listing region: compat_keys
   1.0-triangle/.style={
     /forest/triangle/.style={
       @@deprecated={key "triangle" from v1.0.x. Use key "roof" from library "linguistics" instead},
@@ -100,7 +104,7 @@
       @@deprecated={Key "for all previous" from v1.0.x.  Use key "for preceding siblings" instead.},
       for preceding siblings={##1}},
   },
-  1.0-ignoreinvalidsteps/.code={%
+  1.0-forstep/.code={%
     \def\forest@forstepwrapper##1##2{%
       \def\forest@nodewalk@config@everystep@method{independent}%
       \def\forest@nodewalk@config@history@method{independent}%
@@ -166,5 +170,21 @@
       }%
     }%
   },
+  2.0.2-delayn/.style={
+    /forest/delay@n/.style 2 args={
+      @@deprecated={propagator "delay n" (it introduces two levels of hash doubling)},
+      if={##1==1}{delay={##2}}{delay={delay@n/.wrap pgfmath arg={{####1}{##2}}{##1-1}}}
+    },
+  },
+  2.0.2-wrapnpgfmathargs/.code={
+    \def\forest@wrap@pgfmath@args@@@wrapandpasson{%
+      \forest@deprecated{handler "wrap n pgfmath args" (it introduces two levels of hash doubling)}%
+      \expandafter\expandafter\expandafter\def
+          \expandafter\expandafter\expandafter\forest@wrapped
+          \expandafter\expandafter\expandafter{%
+            \expandafter\forest@wrap@code\forest@wrap@args}%
+      \expandafter\pgfkeysalso\expandafter{\expandafter\pgfkeyscurrentpath\expandafter=\expandafter{\forest@wrapped}}%
+    }%
+  },
 }
 \expandafter\forestcompat\expandafter{\forest@compat}
diff --git a/Master/texmf-dist/tex/latex/forest/forest-index.sty b/Master/texmf-dist/tex/latex/forest/forest-index.sty
index 116666290c4..e470d5ffe9e 100644
--- a/Master/texmf-dist/tex/latex/forest/forest-index.sty
+++ b/Master/texmf-dist/tex/latex/forest/forest-index.sty
@@ -371,12 +371,13 @@
   ]>{@unknown}
 \def\forestindex@filename{\jobname.foridx}
 \IfFileExists{\forestindex@filename}{%
-  \input\forestindex@filename
+  \input\forestindex@filename\relax
 }{}%
 \newwrite\forestindex@out
-\immediate\openout\forestindex@out=\forestindex@filename
+\immediate\openout\forestindex@out=\forestindex@filename.tmp
 \AtEndDocument{%
   \immediate\closeout\forestindex@out
+  \forest@file@copy{\forestindex@filename.tmp}{\forestindex@filename}%
 }
 \endinput
 %%
diff --git a/Master/texmf-dist/tex/latex/forest/forest.sty b/Master/texmf-dist/tex/latex/forest/forest.sty
index a1746c66751..16c96a52e44 100644
--- a/Master/texmf-dist/tex/latex/forest/forest.sty
+++ b/Master/texmf-dist/tex/latex/forest/forest.sty
@@ -44,7 +44,7 @@
 %% - LICENCE
 %% To use the package, only the files marked with + need to be installed.
 %%
-\ProvidesPackage{forest}[2016/03/04 v2.0.2 Drawing (linguistic) trees]
+\ProvidesPackage{forest}[2016/04/09 v2.0.3 Drawing (linguistic) trees]
 
 \RequirePackage{tikz}[2013/12/13]
 \usetikzlibrary{shapes}
@@ -64,13 +64,13 @@
 \newif\ifforest@external@
 \newif\ifforesttikzcshack
 \newif\ifforest@install@keys@to@tikz@path@
-\newif\ifforestdebug
+\newif\ifforestdebugnodewalks
+\newif\ifforestdebugdynamics
 \def\forest@compat{}
 \forestset{package@options/.cd,
   external/.is if=forest@external@,
   tikzcshack/.is if=foresttikzcshack,
   tikzinstallkeys/.is if=forest@install@keys@to@tikz@path@,
-  debug/.is if=forestdebug,
   compat/.store in=\forest@compat,
   compat/.default=most,
   .unknown/.code={% load library
@@ -79,6 +79,10 @@
       \noexpand\forestapplylibrarydefaults{\pgfkeyscurrentname}%
     }%
   },
+  debug/.code={\pgfqkeys{/forest/package@options/debug}{#1}},
+  debug/.default={nodewalks,dynamics},
+  debug/nodewalks/.is if=forestdebugnodewalks,
+  debug/dynamics/.is if=forestdebugdynamics,
 }
 \forest@install@keys@to@tikz@path@true
 \foresttikzcshacktrue
@@ -985,6 +989,7 @@
   \advance\forest@node@maxid1
   \forest@fornode{\the\forest@node@maxid}{%
     \forest@node@init
+    \forestoeset{id}{\forest@cn}%
     \forest@node@setname{node@\forest@cn}%
     \forest@initializefromstandardnode
     \edef#1{\forest@cn}%
@@ -996,6 +1001,7 @@
   \def\forestoinit##1{\ifstrequal{##1}{name}{\forestoset{name}{node@\forest@cn}}{\forestoletO{##1}{#1}{##1}}}%
   \forest@fornode{\the\forest@node@maxid}{%
     \forest@node@init
+    \forestoeset{id}{\forest@cn}%
     \forest@node@setname{\forest@copy@name@template{\forestOve{#1}{name}}}%
     \edef#2{\forest@cn}%
   }%
@@ -1461,7 +1467,6 @@
     \forestOve{#1}{@next}%
   \fi
 }
-
 \def\forest@node@linearpreviousid{%
   \ifnum\forestove{@previous}=0
     \forestove{@parent}%
@@ -1469,20 +1474,87 @@
     \forest@node@previousleafid
   \fi
 }
+
 \def\forest@ifancestorof#1{% is the current node an ancestor of #1? Yes: #2, no: #3
+  \begingroup
   \expandnumberarg\forest@ifancestorof@{\forestOve{#1}{@parent}}%
 }
-\def\forest@ifancestorof@#1#2#3{%
+\def\forest@ifancestorof@#1{%
   \ifnum#1=0
-    \def\forest@ifancestorof@next{\@secondoftwo}%
+    \def\forest@ifancestorof@next{\expandafter\endgroup\@secondoftwo}%
   \else
     \ifnum\forest@cn=#1
-      \def\forest@ifancestorof@next{\@firstoftwo}%
+      \def\forest@ifancestorof@next{\expandafter\endgroup\@firstoftwo}%
     \else
-      \def\forest@ifancestorof@next{\expandnumberarg\forest@ifancestorof@{\forestOve{#1}{@parent}}}%
+      \ifcsdef{forest@circularity@used#1}{%
+        \def\forest@ifancestorof@next{\expandafter\endgroup\@secondoftwo}%
+      }{%
+        \csdef{forest@circularity@used#1}{}%
+        \def\forest@ifancestorof@next{\expandnumberarg\forest@ifancestorof@{\forestOve{#1}{@parent}}}%
+      }%
     \fi
   \fi
-  \forest@ifancestorof@next{#2}{#3}%
+  \forest@ifancestorof@next
+}
+\NewDocumentCommand\forestdebugtypeouttrees{o}{%
+  \forestdebug@typeouttrees\forest@temp
+  \typeout{\IfValueTF{#1}{#1: }{}\forest@temp}%
+}
+\def\forestdebug@typeouttrees#1{% #1 = cs to store the result
+  \begingroup
+  \edef\forest@temp@message{}%
+  \def\forestdebug@typeouttrees@n{0}%
+  \loop
+  \ifnum\forestdebug@typeouttrees@n<\forest@node@maxid
+    \edef\forestdebug@typeouttrees@n{\number\numexpr\forestdebug@typeouttrees@n+1}%
+    \ifcsdef{forestdebug@typeouttree@used@\forestdebug@typeouttrees@n}{}{%
+      \forest@fornode{\forestdebug@typeouttrees@n}{%
+        \begingroup
+        \forestdebug@typeouttrees@findroot
+        \expandafter\endgroup
+        \expandafter\edef\expandafter\forest@cn\expandafter{\forest@cn}%
+        \forestdebug@typeouttree@build
+        \appto\forest@temp@message{\space}%
+      }%
+    }%
+  \repeat
+  \expandafter\endgroup
+  \expandafter\edef\expandafter#1\expandafter{\forest@temp@message}%
+}
+\def\forestdebug@typeouttrees@findroot{%
+  \let\forestdebug@typeouttrees@next\relax
+  \edef\forestdebug@typeouttrees@parent{\forestOve{\forest@cn}{@parent}}%
+  \ifnum\forestdebug@typeouttrees@parent=0
+  \else
+    \ifcsdef{forestdebug@typeouttree@used@\forest@cn}{}{%
+      \csdef{forestdebug@typeouttree@used@\forest@cn}{}%
+      \edef\forest@cn{\forestdebug@typeouttrees@parent}%
+      \let\forestdebug@typeouttrees@next\forestdebug@typeouttrees@findroot
+    }%
+  \fi
+  \forestdebug@typeouttrees@next
+}
+\def\forestdebug@typeouttree#1#2{% #1=root id, #2=cs to receive result
+  \begingroup
+  \edef\forest@temp@message{}%
+  \forest@fornode{#1}{\forestdebug@typeouttree@build}%
+  \expandafter\endgroup
+  \expandafter\edef\expandafter#2\expandafter{\forest@temp@message}%
+}
+\NewDocumentCommand\forestdebugtypeouttree{o m}{%
+  \forestdebug@typeouttree{#1}\forest@temp
+  \typeout{\IfValueTF{#1}{#1: }{}\forest@temp}%
+}
+\def\forestdebug@typeouttree@build{%
+  \eappto\forest@temp@message{[\forest@cn%]
+    \ifcsdef{forestdebug@typeouttree@used@\forest@cn}{*}{}%
+    }%
+  \ifcsdef{forestdebug@typeouttree@used@\forest@cn}{}{%
+    \csdef{forestdebug@typeouttree@used@\forest@cn}{}%
+    \forest@node@foreachchild{\forestdebug@typeouttree@build}%
+  }%
+  \eappto\forest@temp@message{%[
+    ]}%
 }
 \def\forest@declarehandler#1#2#3{%#1=handler for specific type,#2=option name,#3=default value
   \pgfkeyssetvalue{/forest/#2}{#3}%
@@ -1513,8 +1585,6 @@
 \def\forest@declaretoks@handler@A#1#2#3#4#5{% #1=key,#2=path,#3=name,#4=pgfmathname,#5=infix
   \pgfkeysalso{%
     #1/.code={\forestOset{\forest@setter@node}{#3}{##1}},
-    #1+/.code={\forestOappto{\forest@setter@node}{#3}{#5##1}},
-    #2/+#3/.code={\forestOpreto{\forest@setter@node}{#3}{##1#5}},
     #2/if #3/.code n args={3}{%
       \forestoget{#3}\forest@temp@option@value
       \edef\forest@temp@compared@value{\unexpanded{##1}}%
@@ -1537,6 +1607,31 @@
     #2/where #3/.style n args={3}{for tree={#2/if #3={##1}{##2}{##3}}},
     #2/where in #3/.style n args={3}{for tree={#2/if in #3={##1}{##2}{##3}}}
   }%
+  \ifstrempty{#5}{%
+    \pgfkeysalso{%
+      #1+/.code={\forestOappto{\forest@setter@node}{#3}{#5##1}},
+      #2/+#3/.code={\forestOpreto{\forest@setter@node}{#3}{##1#5}},
+    }%
+  }{%
+    \pgfkeysalso{%
+      #1+/.code={%
+        \forestOget{\forest@setter@node}{#3}\forest@temp
+        \ifdefempty{\forest@temp}{%
+          \forestOset{\forest@setter@node}{#3}{##1}%
+        }{%
+          \forestOappto{\forest@setter@node}{#3}{#5##1}%
+        }%
+      },
+      #2/+#3/.code={%
+        \forestOget{\forest@setter@node}{#3}\forest@temp
+        \ifdefempty{\forest@temp}{%
+          \forestOset{\forest@setter@node}{#3}{##1}%
+        }{%
+          \forestOpreto{\forest@setter@node}{#3}{##1#5}%
+        }%
+      }%
+    }%
+  }%
   \pgfkeyssetvalue{#1/option@name}{#3}%
   \pgfkeyssetvalue{#1+/option@name}{#3}%
   \pgfkeyssetvalue{#2/+#3/option@name}{#3}%
@@ -1555,6 +1650,11 @@
   \pgfkeyssetvalue{#2/+#3'/option@name}{#3}%
 }
 \def\forest@declarereadonlydimen@handler#1#2#3#4{% #1=key,#2=path,#3=name,#4=pgfmathname
+  % this is to have `pt` with the correct category code
+  \pgfutil@tempdima=\pgfkeysvalueof{/forest/#3}\relax
+  \edef\forest@marshal{%
+    \noexpand\pgfkeyssetvalue{/forest/#3}{\the\pgfutil@tempdima}%
+  }\forest@marshal
   \pgfkeysalso{%
     #2/if #3/.code n args={3}{%
       \forestoget{#3}\forest@temp@option@value
@@ -1749,20 +1849,35 @@
   declare keylist/.code 2 args={%
     \forest@declarehandler\forest@declarekeylist@handler{#1}{#2}%
   },
-  declare readonly dimen/.code={%
-    \forest@declarehandler\forest@declarereadonlydimen@handler{#1}{}%
+  declare readonly dimen/.code 2 args={%
+    \pgfmathsetlengthmacro\forest@temp{#2}%
+    \edef\forest@marshal{%
+      \unexpanded{\forest@declarehandler\forest@declarereadonlydimen@handler{#1}}{\forest@temp}%
+    }\forest@marshal
   },
   declare dimen/.code 2 args={%
-    \forest@declarehandler\forest@declaredimen@handler{#1}{#2}%
+    \pgfmathsetlengthmacro\forest@temp{#2}%
+    \edef\forest@marshal{%
+      \unexpanded{\forest@declarehandler\forest@declaredimen@handler{#1}}{\forest@temp}%
+    }\forest@marshal
   },
-  declare readonly count/.code={%
-    \forest@declarehandler\forest@declarereadonlycount@handler{#1}{}%
+  declare readonly count/.code 2 args={%
+    \pgfmathtruncatemacro\forest@temp{#2}%
+    \edef\forest@marshal{%
+      \unexpanded{\forest@declarehandler\forest@declarereadonlycount@handler{#1}}{\forest@temp}%
+    }\forest@marshal
   },
   declare count/.code 2 args={%
-    \forest@declarehandler\forest@declarecount@handler{#1}{#2}%
+    \pgfmathtruncatemacro\forest@temp{#2}%
+    \edef\forest@marshal{%
+      \unexpanded{\forest@declarehandler\forest@declarecount@handler{#1}}{\forest@temp}%
+    }\forest@marshal
   },
   declare boolean/.code 2 args={%
-    \forest@declarehandler\forest@declareboolean@handler{#1}{#2}%
+    \pgfmathtruncatemacro\forest@temp{#2}%
+    \edef\forest@marshal{%
+      \unexpanded{\forest@declarehandler\forest@declareboolean@handler{#1}}{\forest@temp}%
+    }\forest@marshal
   },
   /handlers/.restore default value/.code={%
     \edef\forest@handlers@currentpath{\pgfkeyscurrentpath}%
@@ -1796,16 +1911,16 @@
     \pgfmathparse{#2}\let\forest@wrap@arg@i\pgfmathresult
     \edef\forest@wrap@args{{\expandonce\forest@wrap@arg@i}}%
     \def\forest@wrap@code##1{#1}%
+    % here we don't call \forest@wrap@pgfmath@args@@@wrapandpasson, as compat-2.0.2-wrappgfmathargs changes that to achieve the old, confusing state of affairs, which *didn't* apply at *1*-arg pgfmath wrapping
     \expandafter\expandafter\expandafter\forest@temp@toks\expandafter\expandafter\expandafter{\expandafter\forest@wrap@code\forest@wrap@args}%
-    \pgfkeysalso{\pgfkeyscurrentpath/.expand once=\the\forest@temp@toks}%
+    \expandafter\pgfkeysalso\expandafter{\expandafter\pgfkeyscurrentpath\expandafter=\expandafter{\the\forest@temp@toks}}%
   },
   /handlers/.wrap 2 pgfmath args/.code n args={3}{%
     \pgfmathparse{#2}\let\forest@wrap@arg@i\pgfmathresult
     \pgfmathparse{#3}\let\forest@wrap@arg@ii\pgfmathresult
     \edef\forest@wrap@args{{\expandonce\forest@wrap@arg@i}{\expandonce\forest@wrap@arg@ii}}%
     \def\forest@wrap@code##1##2{#1}%
-    \expandafter\expandafter\expandafter\def\expandafter\expandafter\expandafter\forest@wrapped\expandafter\expandafter\expandafter{\expandafter\forest@wrap@code\forest@wrap@args}%
-    \pgfkeysalso{\pgfkeyscurrentpath/.expand once=\forest@wrapped}%
+    \forest@wrap@pgfmath@args@@@wrapandpasson
   },
   /handlers/.wrap 3 pgfmath args/.code n args={4}{%
     \forest@wrap@n@pgfmath@args{#2}{#3}{#4}{}{}{}{}{}{3}%
@@ -1860,8 +1975,15 @@
   \or\def\forest@wrap@code##1##2##3##4##5##6##7{#1}%
   \or\def\forest@wrap@code##1##2##3##4##5##6##7##8{#1}%
   \fi
-  \expandafter\expandafter\expandafter\def\expandafter\expandafter\expandafter\forest@wrapped\expandafter\expandafter\expandafter{\expandafter\forest@wrap@code\forest@wrap@args}%
-  \pgfkeysalso{\pgfkeyscurrentpath/.expand once=\forest@wrapped}%
+  \forest@wrap@pgfmath@args@@@wrapandpasson
+}
+\def\forest@wrap@pgfmath@args@@@wrapandpasson{%
+  \expandafter\expandafter\expandafter\forest@temp@toks
+      \expandafter\expandafter\expandafter{%
+        \expandafter\forest@wrap@code\forest@wrap@args}%
+  \expandafter\pgfkeysalso\expandafter{%
+    \expandafter\pgfkeyscurrentpath\expandafter=\expandafter{%
+        \the\forest@temp@toks}}%
 }
 \newtoks\forest@processargs@result
 \newtoks\forest@processargs@current
@@ -1996,8 +2118,6 @@
 \def\forest@declaretoksregister@handler@A#1#2#3#4#5{% #1=key,#2=path,#3=name,#4=pgfmathname,#5=infix
   \pgfkeysalso{%
     #1/.code={\forestrset{#3}{##1}},
-    #1+/.code={\forestrappto{#3}{#5##1}},
-    #2/+#3/.code={\forestrpreto{#3}{##1#5}},
     #2/if #3/.code n args={3}{%
       \forestrget{#3}\forest@temp@option@value
       \edef\forest@temp@compared@value{\unexpanded{##1}}%
@@ -2018,6 +2138,31 @@
       \fi
     },
   }%
+  \ifstrempty{#5}{%
+    \pgfkeysalso{%
+      #1+/.code={\forestrappto{#3}{#5##1}},
+      #2/+#3/.code={\forestrpreto{#3}{##1#5}},
+    }%
+  }{%
+    \pgfkeysalso{%
+      #1+/.code={%
+        \forestrget{#3}\forest@temp
+        \ifdefempty{\forest@temp}{%
+          \forestrset{#3}{##1}%
+        }{%
+          \forestrappto{#3}{#5##1}%
+        }%
+      },
+      #2/+#3/.code={%
+        \forestrget{#3}\forest@temp
+        \ifdefempty{\forest@temp}{%
+          \forestrset{#3}{##1}%
+        }{%
+          \forestrpreto{#3}{##1#5}%
+        }%
+      }%
+    }%
+  }%
   \pgfkeyssetvalue{#1/option@name}{#3}%
   \pgfkeyssetvalue{#1+/option@name}{#3}%
   \pgfkeyssetvalue{#2/+#3/option@name}{#3}%
@@ -2257,9 +2402,17 @@
   declare dimen register=tempdimc,tempdimc'={0pt},
   declare dimen register=tempdimd,tempdimd'={0pt},
   declare dimen register=tempdimx,tempdimx'={0pt},
+  declare dimen register=tempdimxa,tempdimxa'={0pt},
+  declare dimen register=tempdimxb,tempdimxb'={0pt},
   declare dimen register=tempdimy,tempdimy'={0pt},
+  declare dimen register=tempdimya,tempdimya'={0pt},
+  declare dimen register=tempdimyb,tempdimyb'={0pt},
   declare dimen register=tempdiml,tempdiml'={0pt},
+  declare dimen register=tempdimla,tempdimla'={0pt},
+  declare dimen register=tempdimlb,tempdimlb'={0pt},
   declare dimen register=tempdims,tempdims'={0pt},
+  declare dimen register=tempdimsa,tempdimsa'={0pt},
+  declare dimen register=tempdimsb,tempdimsb'={0pt},
   declare count register=tempcounta,tempcounta'={0},
   declare count register=tempcountb,tempcountb'={0},
   declare count register=tempcountc,tempcountc'={0},
@@ -2309,7 +2462,13 @@
         \@escapeif{\forest@node@setnameoralias{#1@\forest@cn}}%
       \else\@escapeif{%
         \if y\forest@temp@setname
-          \@escapeif{\forest@node@setnameoralias@nameclash{#1}}%
+          \edef\forest@marshal{%
+            \ifstrequal{\forestove{name}}{#1}%
+          }\forest@marshal{%
+            % same name, no problem
+          }{%
+            \@escapeif{\forest@node@setnameoralias@nameclash{#1}}%
+          }%
         \else\@escapeif{% setting an alias: clashing with alias is not a problem
           \forestOget{\forest@node@Nametoid{#1}}{name}\forest@temp
           \expandafter\ifstrequal\expandafter{\forest@temp}{#1}{%
@@ -2489,10 +2648,11 @@
   declare toks={edge label}{},
   declare boolean={phantom}{0},
   baseline/.style={alias={forest@baseline@node}},
-  declare readonly count={n},
-  declare readonly count={n'},
-  declare readonly count={n children},
-  declare readonly count={level},
+  declare readonly count={id}{0},
+  declare readonly count={n}{0},
+  declare readonly count={n'}{0},
+  declare readonly count={n children}{-1},
+  declare readonly count={level}{-1},
   declare dimen=x{0pt},
   declare dimen=y{0pt},
   declare dimen={s}{0pt},
@@ -2502,9 +2662,9 @@
   declare keylist={node options}{anchor=base},
   declare toks={tikz}{},
   afterthought/.style={tikz+={#1}},
-  label/.style={tikz={\path[late options={%
+  label/.style={tikz+={\path[late options={%
         name=\forestoption{name},label={#1}}];}},
-  pin/.style={tikz={\path[late options={%
+  pin/.style={tikz+={\path[late options={%
         name=\forestoption{name},pin={#1}}];}},
   declare toks={content format}{\forestoption{content}},
   plain content/.style={content format={\forestoption{content}}},
@@ -2974,22 +3134,12 @@
     \fi
   }%
 }
-\pgfmathdeclarefunction{id}{1}{%
+\pgfmathdeclarefunction*{id}{1}{%
   \forest@forthis{%
     \forest@nameandgo{#1}%
     \let\pgfmathresult\forest@cn
   }%
 }
-\forestset{%
-  if id/.code n args={3}{%
-    \ifnum#1=\forest@cn\relax
-      \pgfkeysalso{#2}%
-    \else
-      \pgfkeysalso{#3}%
-    \fi
-  },
-  where id/.style n args={3}{for tree={if id={#1}{#2}{#3}}}
-}
 \def\forest@nodewalk@n{0}
 \def\forest@nodewalk@historyback{0,}
 \def\forest@nodewalk@historyforward{0,}
@@ -3061,7 +3211,7 @@
   \fi
 }
 \def\forest@nodewalk@makestep@oninvalid@step{\forest@nodewalk@makestep@}
-\def\forest@nodewalk@makestep@oninvalid@error{\PackageError{forest}{nodewalk stepped to the invalid node; stack: "\forest@nodewalk@currentstepname"}{}}%
+\def\forest@nodewalk@makestep@oninvalid@error{\PackageError{forest}{nodewalk stepped to the invalid node\MessageBreak nodewalk stack: "\forest@nodewalk@currentstepname"}{}}%
 \let\forest@nodewalk@makestep@oninvalid@fake\relax
 \def\forest@nodewalk@makestep@oninvalid@compatfake{%
   \forest@deprecated{last step in stack "\forest@nodewalk@currentstepname", which stepped on an invalid node; enabled by "compat=ignoreinvalidsteps".  Use "on invalid={fake}{...}" or "for Nodewalk={on invalid=fake}{...}{...}" instead.}%
@@ -3073,7 +3223,7 @@
     \edef\forest@nodewalk@n{\number\numexpr\forest@nodewalk@n+1}%
     \epreto\forest@nodewalk@historyback{\forest@cn,}%
     \def\forest@nodewalk@historyforward{0,}%
-    \ifforestdebug\forest@nodewalk@makestep@debug\fi
+    \ifforestdebugnodewalks\forest@nodewalk@makestep@debug\fi
     \forest@process@keylist@register{every step}%
   \fi
 }
@@ -3082,9 +3232,6 @@
     \noexpand\typeout{\ifforest@nodewalk@fake fake \fi "\forest@nodewalk@currentstepname" step to node id=\forest@cn, content=\forestoption{content}}%
   }\forest@marshal
 }%
-\forestset{
-  debug/.is if=forestdebug,
-}
 \def\forest@handlers@savecurrentpath{%
   \edef\pgfkeyscurrentkey{\pgfkeyscurrentpath}%
   \let\forest@currentkey\pgfkeyscurrentkey
@@ -3150,9 +3297,9 @@
     \fi
     \pretotoks\forest@temp@toks{\appto\forest@nodewalk@currentstepname{,#1}}%
     \expandafter\forest@temp@toks\expandafter{\expandafter\forest@saveandrestoremacro\expandafter\forest@nodewalk@currentstepname\expandafter{\the\forest@temp@toks}}%
-    \ifforestdebug
-      \epretotoks\forest@temp@toks{\noexpand\typeout{Starting step "#1" from id=\forest@cn
-          \ifnum\forest@nodewalkstephandler@nargs>0 with args ####1\fi
+    \ifforestdebugnodewalks
+      \epretotoks\forest@temp@toks{\noexpand\typeout{Starting step "#1" from id=\noexpand\forest@cn
+          \ifnum\forest@nodewalkstephandler@nargs>0 \space with args ####1\fi
           \ifnum\forest@nodewalkstephandler@nargs>1 ,####2\fi
           \ifnum\forest@nodewalkstephandler@nargs>2 ,####3\fi
           \ifnum\forest@nodewalkstephandler@nargs>3 ,####4\fi
@@ -3396,36 +3543,30 @@
   %%% end nodewalk config
 }
 \forestset{
-  define long step={branch}{n args=1,@bare,style}{%
-    branch@@build/.style={branch@build={##1}{}},
-    @branch={#1},
-  },
-  define long step={branch'}{n args=1,@bare,style}{%
-    branch@@build/.style/.expanded={branch@build={####1}{\forestregister{every step},}},
-    @branch={#1},
-  },
-  nodewalk/@branch/.style={
-    TeX={\forest@temp@toks{}},
-    split/.process args={r}{#1}{,}{branch@@build},
-    branch@do,
-  },
-  nodewalk/branch@build/.code 2 args={% #1 = nodewalk for this branch, #2 = perhaps every step keylist
-    \ifstrempty{#1}{}{%
-      \expandafter\ifstrempty\expandafter{\the\forest@temp@toks}{%
-        \edef\forest@marshal{%
-          \noexpand\forest@temp@toks{for nodewalk={\unexpanded{#1}}{\forestregister{every step}}}%
-        }\forest@marshal
-      }{%
-        \edef\forest@marshal{%
-          \noexpand\forest@temp@toks{for nodewalk={\unexpanded{#1}}{#2\the\forest@temp@toks}}%
-        }\forest@marshal
-      }%
-    }%
+  declare toks register=branch@temp@toks,
+  branch@temp@toks={},
+  declare keylist register=branched@nodewalk,
+  branched@nodewalk={},
+  define long step={branch}{n args=1,@bare,style}{@branch={#1}{branch@build@realstep,branch@build@fakestep}},
+  define long step={branch'}{n args=1,@bare,style}{@branch={#1}{branch@build@realstep}},
+  @branch/.style 2 args={%
+    save and restore register={branched@nodewalk}{
+      branch@temp@toks={},
+      split/.process args={r}{#1}{,}{#2},
+      branch@temp@style/.style/.register=branch@temp@toks,
+      branch@temp@style,
+      branch@temp@style/.style/.register=branched@nodewalk,
+      branch@temp@style,
+    }
   },
-  nodewalk/branch@do/.code={%
-    \edef\forest@marshal{%
-      \noexpand\pgfkeysalso{fake={\the\forest@temp@toks}}%
-    }\forest@marshal
+  nodewalk/branch@build@realstep/.style={% #1 = nodewalk for this branch
+    branch@temp@toks/.expanded={for nodewalk={\unexpanded{#1}}{
+        branched@nodewalk+/.expanded={id=\noexpand\forestoption{id}},
+        \forestregister{branch@temp@toks}}},
+  },
+  nodewalk/branch@build@fakestep/.style={% #1 = nodewalk for this branch
+    branch@temp@toks/.expanded={for nodewalk={\unexpanded{#1}}{
+        \forestregister{branch@temp@toks}}},
   },
   define long step={group}{autostep}{\forest@go{#1}},
   nodewalk/fake/.code={%
@@ -3440,8 +3581,18 @@
       \pgfkeysalso{#1}%
     }%
   },
+  declare keylist register=filtered@nodewalk,
+  filtered@nodewalk={},
   define long step={filter}{n args=2,@bare,style}{% #1 = nodewalk, #2 = condition
-    nodewalk/.expanded={\unexpanded{#1}}{if={\unexpanded{#2}}{\forestregister{every step}}{}}{}
+    save and restore register={filtered@nodewalk}{
+      filtered@nodewalk'={},
+      Nodewalk=%
+        {history=inherited}%
+        {#1}%
+        {if={#2}{filtered@nodewalk+/.expanded={id=\forestoption{id}}}{}},
+      filtered@nodewalk@style/.style/.register=filtered@nodewalk,
+      filtered@nodewalk@style
+    }
   },
   on@invalid/.is choice,
   on@invalid/error/.code={},
@@ -4012,11 +4163,19 @@
   },
   define long step={level<}{n args=1}{%
     \pgfmathtruncatemacro\forest@temp{(#1)-1}%
-    \edef\forest@marshal{%
-      \noexpand\forest@node@foreach@breadthfirst
-        {\forest@temp}%
-        {\noexpand\forest@nodewalk@makestep}%
-    }\forest@marshal
+    \show\forest@temp
+    \ifnum\forest@temp=-1
+      % special case, as \forest@node@foreach@breadthfirst uses level<0 as a signal for unlimited max level
+      \ifnum\forestove{level}=0
+        \forest@nodewalk@makestep
+      \fi
+    \else
+      \edef\forest@marshal{%
+        \noexpand\forest@node@foreach@breadthfirst
+          {\forest@temp}%
+          {\noexpand\forest@nodewalk@makestep}%
+      }\forest@marshal
+    \fi
   },
   define long step={level reversed}{n args=1}{%
     \pgfmathtruncatemacro\forest@temp{#1}%
@@ -4183,28 +4342,61 @@
     \noexpand\forestrset{#1}{\forestregister{#1}}%
   }\forest@marshal
 }
+\forestset{
+  save and restore register/.code 2 args={%
+    \forest@saveandrestoreregister{filter@ed}{%
+      \pgfkeysalso{#2}%
+    }%
+  },
+}
 \def\forest@remove@node#1{%
+  \ifforestdebugdynamics\forestdebug@dynamics{before removing #1}\fi
   \forest@node@Remove{#1}%
 }
 \def\forest@append@node#1#2{%
+  \ifforestdebugdynamics\forestdebug@dynamics{before appending #2 to #1}\fi
+  \forest@dynamic@circularitytest{#2}{#1}{append}%
   \forest@node@Remove{#2}%
   \forest@node@Append{#1}{#2}%
 }
 \def\forest@prepend@node#1#2{%
+  \ifforestdebugdynamics\forestdebug@dynamics{before prepending #2 to #1}\fi
+  \forest@dynamic@circularitytest{#2}{#1}{prepend}%
   \forest@node@Remove{#2}%
   \forest@node@Prepend{#1}{#2}%
 }
 \def\forest@insertafter@node#1#2{%
+  \ifforestdebugdynamics\forestdebug@dynamics{before inserting #2 after #1}\fi
   \forest@node@Remove{#2}%
   \forest@node@Insertafter{\forestOve{#1}{@parent}}{#2}{#1}%
 }
 \def\forest@insertbefore@node#1#2{%
+  \ifforestdebugdynamics\forestdebug@dynamics{before inserting #2 before #1}\fi
   \forest@node@Remove{#2}%
   \forest@node@Insertbefore{\forestOve{#1}{@parent}}{#2}{#1}%
 }
 \def\forest@set@root#1#2{%
+  \ifforestdebugdynamics\forestdebug@dynamics{before setting #1 as root}\fi
   \def\forest@root{#2}%
 }
+\def\forest@dynamic@circularitytest#1#2#3{%
+  % #1=potenitial ancestor,#2=potential descendant, #3=message prefix
+  \ifnum#1=#2
+    \forest@circularityerror{#1}{#2}{#3}%
+  \else
+    \forest@fornode{#1}{%
+      \forest@ifancestorof{#2}{\forest@circularityerror{#1}{#2}{#3}}{}%
+    }%
+  \fi
+}
+\def\forest@circularityerror#1#2#3{%
+  \forestdebug@typeouttrees{\forest@temp}%
+  \PackageError{forest}{#3ing node id=#1 to id=#2 would result in a circular tree\MessageBreak forest of ids: \forest@temp}{}%
+}%
+\def\forestdebug@dynamics#1{%
+  \forestdebug@typeouttrees\forest@temp
+  \typeout{#1: \forest@temp}%
+}
 \def\forest@appto@do@dynamics#1#2{%
    \forest@nodehandleby@name@nodewalk@or@bracket{#2}%
    \ifcase\forest@dynamics@copyhow\relax\or
@@ -4294,8 +4486,10 @@
   \fi
 }
 \def\forest@nodesort#1#2#3{% #1 = direction, #2 = parent node, #3 = sort key
+  \ifforestdebugdynamics\forestdebug@dynamics{before sorting children of #2}\fi
   \def\forest@nodesort@sortkey{#3}%
   \forest@fornode{#2}{\forest@nodesort@#1}%
+  \ifforestdebugdynamics\forestdebug@dynamics{after sorting children of #2}\fi
 }
 \def\forest@nodesort@#1{%
   % prepare the array of child ids
@@ -4404,7 +4598,7 @@
   declare keylist={delay}{},
   delay n/.style 2 args={if={#1==0}{#2}{delay@n={#1}{#2}}},
   delay@n/.style 2 args={
-    if={#1==1}{delay={#2}}{delay={delay@n/.wrap pgfmath arg={{##1}{#2}}{#1-1}}}
+    if={#1==1}{delay={#2}}{delay={delay@n/.process args={P}{#1-1}{#2}}}
   },
   if have delayed/.style 2 args={if have delayed'={processing order}{#1}{#2}},
   if have delayed'/.code n args=3{%
@@ -4468,10 +4662,21 @@
   },
   %%% end listing region: draw_tree_method
   draw tree node/.code={\forest@draw@node},
-  draw tree edge/.code={\forest@draw@edge},
-  draw tree tikz/.code={\forest@draw@tikz},
   draw tree node'/.code={\forest@draw@node@},
+  if node drawn/.code n args={3}{%
+    \forest@forthis{%
+      \forest@configured@nodewalk{independent}{inherited}{fake}{#1}{}%
+      \ifnum\forest@cn=0
+        \forest@tempfalse
+      \else
+        \ifcsdef{forest@drawn@\forest@cn}{\forest@temptrue}{\forest@tempfalse}%
+      \fi
+    }%
+    \ifforest@temp\pgfkeysalso{#2}\else\pgfkeysalso{#3}\fi
+  },
+  draw tree edge/.code={\forest@draw@edge},
   draw tree edge'/.code={\forest@draw@edge@},
+  draw tree tikz/.code={\forest@draw@tikz@}, % always!
   draw tree tikz'/.code={\forest@draw@tikz@},
   processing order/.nodewalk style={tree},
   %given options processing order/.style={processing order},
@@ -4598,16 +4803,16 @@
 }
 
 \forestset{
-  declare readonly dimen={min x},
-  declare readonly dimen={min y},
-  declare readonly dimen={max x},
-  declare readonly dimen={max y},
+  declare readonly dimen={min x}{0pt},
+  declare readonly dimen={min y}{0pt},
+  declare readonly dimen={max x}{0pt},
+  declare readonly dimen={max y}{0pt},
 }
 \def\forest@patch@enormouscoordinateboxbounds@plus#1{%
-  \expandafter\ifstrequal\expandafter{#1}{16000.0pt}{\def#1{0.0pt}}{}%
+  \expandafter\ifstrequal\expandafter{#1}{16000.0pt}{\edef#1{0.0\pgfmath@pt}}{}%
 }
 \def\forest@patch@enormouscoordinateboxbounds@minus#1{%
-  \expandafter\ifstrequal\expandafter{#1}{-16000.0pt}{\def#1{0.0pt}}{}%
+  \expandafter\ifstrequal\expandafter{#1}{-16000.0pt}{\edef#1{0.0\pgfmath@pt}}{}%
 }
 \def\forest@positionnodelater@save{%
   \global\setbox\forest@box=\box\pgfpositionnodelaterbox
@@ -4649,28 +4854,30 @@
   \pgfsyssoftpath@setcurrentpath\forest@pack@original@path
 }
 \def\forest@@pack{%
-  \ifnum\forestove{n children}>0
-    \ifnum\forestove{uniform growth}>0
+  \ifnum\forestove{uniform growth}>0
+    \ifnum\forestove{n children}>0
       \forest@pack@level@uniform
       \forest@pack@aligntiers@ofsubtree
       \forest@pack@sibling@uniform@recursive
-    \else
-      \forest@node@foreachchild{\forest@@pack}%
-      \forest@process@hook@keylist@nodynamics{before packing node}{current}%
+    \fi
+  \else
+    \forest@node@foreachchild{\forest@@pack}%
+    \forest@process@hook@keylist@nodynamics{before packing node}{current}%
+    \ifnum\forestove{n children}>0
       \forest@pack@level@nonuniform
       \forest@pack@aligntiers
       \forest@pack@sibling@uniform@applyreversed
     \fi
+    \forestoget{after packing node}\forest@temp@keys
+    \forest@process@hook@keylist@nodynamics{after packing node}{current}%
   \fi
-  \forestoget{after packing node}\forest@temp@keys
-  \forest@process@hook@keylist@nodynamics{after packing node}{current}%
 }
 \def\forest@pack@onlythisnode{%
   \ifnum\forestove{n children}>0
     \forest@pack@computetiers
     \forest@pack@level@nonuniform
     \forest@pack@aligntiers
-    \forest@node@foreachchild{\forestoset{s}{0pt}}%
+    \forest@node@foreachchild{\forestoset{s}{0\pgfmath@pt}}%
     \forest@pack@sibling@uniform@applyreversed
   \fi
 }
@@ -4823,7 +5030,7 @@
   \let\forest@previous@positive@edge\pgfutil@empty
   \forest@extendpath\forest@previous@positive@edge\forest@temp@edge{}%
   \forestOget{\forest@child}{@#3}\forest@child
-  \edef\forest@previous@child@s{0pt}%
+  \edef\forest@previous@child@s{0\pgfmath@pt}%
   \safeloop
   \unless\ifnum\forest@child=0
     \edef\forest@temp{%
@@ -5780,6 +5987,7 @@
 }
 \def\forest@drawtree@root{0}
 \def\forest@node@drawtree@{%
+  \def\forest@clear@drawn{}%
   \forest@forthis{%
     \forest@saveandrestoremacro\forest@drawtree@root{%
       \edef\forest@drawtree@root{\forest@cn}%
@@ -5787,14 +5995,18 @@
     }%
   }%
   \forest@node@Ifnamedefined{forest@baseline@node}{%
-    \edef\forest@temp{%
-      \noexpand\pgfsetbaselinepointlater{%
-        \noexpand\pgfpointanchor
-          {\forestOve{\forest@node@Nametoid{forest@baseline@node}}{name}}
-          {\forestOve{\forest@node@Nametoid{forest@baseline@node}}{anchor}}
-      }%
-    }\forest@temp
+    \edef\forest@baseline@id{\forest@node@Nametoid{forest@baseline@node}}%
+    \ifcsdef{forest@drawn@\forest@baseline@id}{%
+      \edef\forest@marshal{%
+        \noexpand\pgfsetbaselinepointlater{%
+          \noexpand\pgfpointanchor
+            {\forestOve{\forest@baseline@id}{name}}%
+            {\forestOve{\forest@baseline@id}{anchor}}%
+        }%
+      }\forest@marshal
+    }{}%
   }{}%
+  \forest@clear@drawn
 }
 \def\forest@draw@node{%
   \ifnum\forestove{phantom}=0
@@ -5810,15 +6022,18 @@
   \ifforest@drawtree@preservenodeboxes@
     \pgfnodealias{\forestove{later@name}}{forest@temp}%
   \fi
+  \csdef{forest@drawn@\forest@cn}{}%
+  \eappto\forest@clear@drawn{\noexpand\csundef{forest@drawn@\forest@cn}}%
 }
 \def\forest@draw@edge{%
-  \ifnum\forest@cn=\forest@drawtree@root\relax\else
-    \ifnum\forestove{phantom}=0
-      \ifnum\forestOve{\forestove{@parent}}{phantom}=0
+  \ifcsdef{forest@drawn@\forest@cn}{% was the current node drawn?
+    \ifnum\forestove{@parent}=0 % do we have a parent?
+    \else
+      \ifcsdef{forest@drawn@\forestove{@parent}}{% was the parent drawn?
         \forest@draw@edge@
-      \fi
+      }{}%
     \fi
-  \fi
+  }{}%
 }
 \def\forest@draw@edge@{%
   \edef\forest@temp{\forestove{edge path}}\forest@temp
@@ -6561,24 +6776,39 @@
   \ifdim#2>\pgf@yb\relax\pgf@yb=#2 \fi
 }
 \pgfkeys{/forest/external/.cd,
-  copy command/.initial={cp "\source" "\target"},
+  %copy command/.initial={cp "\source" "\target"},
+  copy command/.initial={},
   optimize/.is if=forest@external@optimize@,
   context/.initial={%
     \forestOve{\csname forest@id@of@standard node\endcsname}{environment@formula}},
   depends on macro/.style={context/.append/.expanded={%
       \expandafter\detokenize\expandafter{#1}}},
 }
-\def\forest@external@copy#1#2{%
-  \pgfkeysgetvalue{/forest/external/copy command}\forest@copy@command
-  \ifx\forest@copy@command\pgfkeysnovalue\else
-    \IfFileExists{#1}{%
-      {%
-        \def\source{#1}%
-        \def\target{#2}%
-        \immediate\write18{\forest@copy@command}%
-      }%
-    }{}%
-  \fi
+\def\forest@file@copy#1#2{%
+  \IfFileExists{#1}{%
+    \pgfkeysgetvalue{/forest/external/copy command}\forest@copy@command
+    \ifdefempty\forest@copy@command{%
+      \forest@file@copy@{#1}{#2}%
+    }{ % copy by external command
+      \def\source{#1}%
+      \def\target{#2}%
+      \immediate\write18{\forest@copy@command}%
+    }%
+  }{}%
+}
+\def\forest@file@copy@#1#2{%
+  \newread\forest@copy@in
+  \openin\forest@copy@in=#1
+  \newwrite\forest@copy@out
+  \immediate\openout\forest@copy@out#2
+  \endlinechar-1
+  \loop
+  \unless\ifeof\forest@copy@in
+    \readline\forest@copy@in to\forest@temp
+    \immediate\write\forest@copy@out{\forest@temp}%
+  \repeat
+  \immediate\closeout\forest@copy@out
+  \closein\forest@copy@in
 }
 \newif\ifforest@external@optimize@
 \forest@external@optimize@true
@@ -6601,13 +6831,13 @@
     /pgf/images/aux in dpth=false,
   }%
   \tikzifexternalizing{}{%
-    \forest@external@copy{\jobname.aux}{\jobname.aux.copy}%
+    \forest@file@copy{\jobname.aux}{\jobname.aux.copy}%
   }%
   \AtBeginDocument{%
     \tikzifexternalizing{%
       \IfFileExists{\tikzexternalrealjob.aux.copy}{%
         \makeatletter
-        \input \tikzexternalrealjob.aux.copy
+        \input\tikzexternalrealjob.aux.copy\relax
         \makeatother
       }{}%
     }{%
@@ -6617,14 +6847,14 @@
     \IfFileExists{\tikzexternalrealjob.for}{%
       {%
         \makehashother\makeatletter
-        \input \tikzexternalrealjob.for
+        \input\tikzexternalrealjob.for\relax
       }%
     }{}%
   }%
   \AtEndDocument{%
     \tikzifexternalizing{}{%
       \immediate\closeout\forest@auxout
-      \forest@external@copy{\jobname.for.tmp}{\jobname.for}%
+      \forest@file@copy{\jobname.for.tmp}{\jobname.for}%
     }%
   }%
 \fi
@@ -6810,6 +7040,7 @@
   \advance\forest@node@maxid1
   \forest@fornode{\the\forest@node@maxid}{%
     \forest@node@init
+    \forestoeset{id}{\forest@cn}%
     \forest@node@setname@silent{standard node}%
   }%
 }