test(gd)!: New test set and its first test

The gd test set only runs on LuaTeX.

`pgfgd-debug.lua` adds debugging code to `InterfaceToDisplay` functions
which helps in checking tests based on states of display layer (Lua),
rather than box content.

Signed-off-by: muzimuzhi <[email protected]>

build.lua

@@ -40,6 +40,9 @@ specialformats["latex"] = specialformats["latex"] or
   }
 checkengines = {"pdftex", "latexdvips", "latexdvisvgm", "luatex", "xetex"}
 
+-- Use multiple sets of tests
+checkconfigs = { "build", "config-gd" }
+
 --- Keep all \special data (may one day be the l3build default)
 maxprintline = 9999
 

config-gd.lua

@@ -0,0 +1,5 @@
+-- Tests for graph drawing (gd) library
+
+stdengine    = "luatex"
+checkengines = {"luatex"}
+testfiledir  = "testfiles-gd"

testfiles-gd/support/pgfgd-debug.lua

@@ -0,0 +1,39 @@
+local InterfaceToDisplay = pgf.gd.interface.InterfaceToDisplay
+
+--- Wrap InterfaceToDisplay functions to prepend debugging code
+local createVertex = InterfaceToDisplay.createVertex
+-- here `...` is a vararg expression, 
+-- see https://www.lua.org/manual/5.3/manual.html#3.4.11
+function InterfaceToDisplay.createVertex(...)
+  local name = ...
+  debug("Create vertex '%s'", name)
+  createVertex(...)
+end
+
+local createEdge = InterfaceToDisplay.createEdge
+function InterfaceToDisplay.createEdge(...)
+  local tail, head, direction = ...
+  debug("Create edge '%s' from '%s' to '%s'", direction, tail, head)
+  createEdge(...)
+end
+
+-- this generates too many debug lines
+-- local createEvent = InterfaceToDisplay.createEvent
+-- function InterfaceToDisplay.createEvent(...)
+--   local kind = ...
+--   debug("Create event '%s'", kind)
+--   return createEvent(...)
+-- end
+
+local addToVertexOptions = InterfaceToDisplay.addToVertexOptions
+function InterfaceToDisplay.addToVertexOptions(...)
+  local name = ...
+  debug("Add options to vetex '%s'", name)
+  addToVertexOptions(...)
+end
+
+
+-- helper
+function debug(format_str, ...)
+  tex.sprint(string.format("\\pgfgdluainfo{" .. format_str .. "}", ...))
+end

testfiles-gd/support/pgfgd-regression-test.tex

@@ -0,0 +1,18 @@
+% This file should be loaded _after_ graphdrawing.
+\input regression-test.tex
+
+\catcode`\@=11 % \makeatletter
+
+\def\pgfgdBeforeBeginDocument{
+  % redirect error
+  \def\pgfutil@packageerror#1#2#3{\immediate\write17{Package #1 Error: #2.}}
+
+  % new message type "info"
+  \def\pgftest@genericinfo#1#2{\immediate\write17{#1 Info: #2.}}
+  \def\pgfgdluainfo{\pgftest@genericinfo{Gd Lua layer}}
+
+  % insert debugging code
+  \directlua{dofile('pgfgd-debug.lua')}
+}
+
+\catcode`\@=12 % \makeatother

testfiles-gd/tikz-gd-gh1087.lvt

@@ -0,0 +1,41 @@
+\documentclass{minimal}
+\input{pgfgd-regression-test}
+
+\RequirePackage{tikz}
+\usetikzlibrary{graphs, graphdrawing}
+\usegdlibrary{layered}
+
+\pgfgdBeforeBeginDocument
+\begin{document}
+
+\START
+
+% use all five edge kinds
+\def\testgraph{ a -> {b, c <-> d} -- e <- f; a -!- f; }
+\SEPARATOR
+\TYPE{Graph: \testgraph}
+\SEPARATOR
+
+\BEGINTEST{Non-empty `name prefix`}
+\tikzpicture[name prefix=x-]
+  \graph[layered layout] { [parse/.expand once=\testgraph] };
+
+  % works
+  \path (b) (x-b);
+  \path[name prefix=]   (x-b);
+  \path[name prefix=y-] (x-b);
+
+  % throws errors
+  \path[name prefix=] (b);
+\endtikzpicture
+\ENDTEST
+
+\BEGINTEST{Empty `name prefix`}
+\tikzpicture
+  \graph[layered layout] { [parse/.expand once=\testgraph] };
+  \path (b);
+  \path[name prefix=z-] (b);
+\endtikzpicture
+\ENDTEST
+
+\END

testfiles-gd/tikz-gd-gh1087.tlg

@@ -0,0 +1,48 @@
+This is a generated file for the l3build validation system.
+Don't change this file in any respect.
+============================================================
+Graph:  a -> {b, c <-> d} -- e <- f; a -!- f; 
+============================================================
+============================================================
+TEST 1: Non-empty `name prefix`
+============================================================
+Gd Lua layer Info: Create vertex 'x-a'.
+Gd Lua layer Info: Create vertex 'x-b'.
+Gd Lua layer Info: Create vertex 'x-c'.
+Gd Lua layer Info: Create vertex 'x-d'.
+Gd Lua layer Info: Create edge '<->' from 'x-c' to 'x-d'.
+Gd Lua layer Info: Create edge '->' from 'x-a' to 'x-b'.
+Gd Lua layer Info: Create edge '->' from 'x-a' to 'x-c'.
+Gd Lua layer Info: Create vertex 'x-e'.
+Gd Lua layer Info: Create edge '--' from 'x-b' to 'x-e'.
+Gd Lua layer Info: Create edge '--' from 'x-d' to 'x-e'.
+Gd Lua layer Info: Create vertex 'x-f'.
+Gd Lua layer Info: Create edge '<-' from 'x-e' to 'x-f'.
+Gd Lua layer Info: Add options to vetex 'x-a'.
+Gd Lua layer Info: Add options to vetex 'x-a'.
+Gd Lua layer Info: Add options to vetex 'x-f'.
+Gd Lua layer Info: Add options to vetex 'x-f'.
+Gd Lua layer Info: Create edge '-!-' from 'x-a' to 'x-f'.
+Package pgf Error: No shape named `b' is known.
+============================================================
+============================================================
+TEST 2: Empty `name prefix`
+============================================================
+Gd Lua layer Info: Create vertex 'a'.
+Gd Lua layer Info: Create vertex 'b'.
+Gd Lua layer Info: Create vertex 'c'.
+Gd Lua layer Info: Create vertex 'd'.
+Gd Lua layer Info: Create edge '<->' from 'c' to 'd'.
+Gd Lua layer Info: Create edge '->' from 'a' to 'b'.
+Gd Lua layer Info: Create edge '->' from 'a' to 'c'.
+Gd Lua layer Info: Create vertex 'e'.
+Gd Lua layer Info: Create edge '--' from 'b' to 'e'.
+Gd Lua layer Info: Create edge '--' from 'd' to 'e'.
+Gd Lua layer Info: Create vertex 'f'.
+Gd Lua layer Info: Create edge '<-' from 'e' to 'f'.
+Gd Lua layer Info: Add options to vetex 'a'.
+Gd Lua layer Info: Add options to vetex 'a'.
+Gd Lua layer Info: Add options to vetex 'f'.
+Gd Lua layer Info: Add options to vetex 'f'.
+Gd Lua layer Info: Create edge '-!-' from 'a' to 'f'.
+============================================================