pkgconfig module: allow custom variables to reference builtin directories

Automatically generate additional variables and write them into the
generated pkg-config file.

This means projects no longer need to manually define the ones they
use, which is annoying for dataonly usages (it used to forbid setting
the base library-relevant "reserved" ones, and now allows it only for
dataonly. But it's bloat to manualy list them anyway).

It also fixes a regression in commit
248e6cf4736ef9ec636228da66c28f9be03aa74f which caused libdir to not be
set, and to be unsettable, if the pkg-config file has no libraries but
uses the ${libdir} expansion in a custom variable. This could be
considered likely a case for dataonly, but it's not guaranteed.

2 files changed, 30 insertions, 1 deletions

diff --git a/test cases/common/44 pkgconfig-gen/meson.build b/test cases/common/44 pkgconfig-gen/meson.build
index 128205a..a24c239 100644
--- a/test cases/common/44 pkgconfig-gen/meson.build
+++ b/test cases/common/44 pkgconfig-gen/meson.build
@@ -1,4 +1,4 @@
-project('pkgconfig-gen', 'c')
+project('pkgconfig-gen', 'c', meson_version: '>=0.60.0')
 
 # Some CI runners does not have zlib, just skip them as we need some common
 # external dependency.
@@ -149,3 +149,17 @@ ct = custom_target('stat3',
 )
 simple6 = library('simple6', link_with: ct)
 pkgg.generate(simple6)
+
+# implicit variables
+pkgg.generate(
+  name : 'libvartest',
+  description : 'Check that implicit vars are created',
+  version : libver,
+  variables: ['datadir=${prefix}/data', 'foo=${datadir}/foo', 'bar=${bindir}/bar']
+)
+pkgg.generate(
+  name : 'libvartest2',
+  description : 'Check that libdir is not an implicit var',
+  version : libver,
+  variables: ['bar=${libdir}/bar']
+)
diff --git a/test cases/common/44 pkgconfig-gen/test.json b/test cases/common/44 pkgconfig-gen/test.json
index c7bdd43..118fecd 100644
--- a/test cases/common/44 pkgconfig-gen/test.json
+++ b/test cases/common/44 pkgconfig-gen/test.json
@@ -7,11 +7,26 @@
     {"type": "file", "file": "usr/lib/pkgconfig/libfoo.pc"},
     {"type": "file", "file": "usr/lib/pkgconfig/libhello.pc"},
     {"type": "file", "file": "usr/lib/pkgconfig/libhello_nolib.pc"},
+    {"type": "file", "file": "usr/lib/pkgconfig/libvartest.pc"},
+    {"type": "file", "file": "usr/lib/pkgconfig/libvartest2.pc"},
     {"type": "file", "file": "usr/lib/pkgconfig/simple2.pc"},
     {"type": "file", "file": "usr/lib/pkgconfig/simple3.pc"},
     {"type": "file", "file": "usr/lib/pkgconfig/simple5.pc"},
     {"type": "file", "file": "usr/lib/pkgconfig/simple6.pc"},
     {"type": "file", "file": "usr/lib/pkgconfig/ct.pc"},
     {"type": "file", "file": "usr/lib/pkgconfig/ct0.pc"}
+  ],
+  "stdout": [
+    {
+      "line": "test cases/common/44 pkgconfig-gen/meson.build:158: WARNING: Project targeting '>=0.60.0' but tried to use feature introduced in '0.62.0': pkgconfig.generate implicit variable for builtin directories."
+    },
+    {
+      "line": "test cases/common/44 pkgconfig-gen/meson.build:164: WARNING: Project targeting '>=0.60.0' but tried to use feature introduced in '0.62.0': pkgconfig.generate implicit variable for builtin directories.",
+      "count": 0
+    },
+    {
+      "comment": "This will either match in the future-deprecated notice summary, or match the warning summary",
+      "line": " * 0.62.0: {'pkgconfig.generate variable for builtin directories'}"
+    }
   ]
 }