Meson build: Make it possible to use sigc++ as a subproject

mm-common can be a subproject of sigc++.

7 files changed, 42 insertions, 16 deletions

diff --git a/Makefile.am b/Makefile.am
index 4c24f42..9a6f4a8 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -49,6 +49,7 @@ EXTRA_DIST = \
   docs/reference/meson.build \
   examples/meson.build \
   sigc++/meson.build \
+  subprojects/mm-common.wrap \
   tests/meson.build \
   tools/handle-built-files.py \
   tools/tutorial-custom-cmd.py \
diff --git a/docs/reference/meson.build b/docs/reference/meson.build
index 4eb402d..c968bfe 100644
--- a/docs/reference/meson.build
+++ b/docs/reference/meson.build
@@ -4,7 +4,7 @@
 #        sigcxx_api_version, build_documentation, source_h_files,
 #        built_h_files, install_datadir, python3, doc_reference,
 #        built_h_file_targets
-# Output: install_docdir, install_devhelpdir
+# Output: install_docdir, install_devhelpdir, tag_file
 
 tag_file_modules = [
   'mm-common-libstdc++',
@@ -14,9 +14,9 @@ docinstall_flags = []
 foreach module : tag_file_modules
   depmod = dependency(module, required: false)
   if depmod.found()
-    doxytagfile = depmod.get_pkgconfig_variable('doxytagfile')
-    htmlrefpub = depmod.get_pkgconfig_variable('htmlrefpub', default: '')
-    htmlrefdir = depmod.get_pkgconfig_variable('htmlrefdir', default: '')
+    doxytagfile = depmod.get_variable(pkgconfig: 'doxytagfile', internal: 'doxytagfile')
+    htmlrefpub = depmod.get_variable(pkgconfig: 'htmlrefpub', internal: 'htmlrefpub', default_value: '')
+    htmlrefdir = depmod.get_variable(pkgconfig: 'htmlrefdir', internal: 'htmlrefdir', default_value: '')
     if htmlrefpub == ''
       htmlrefpub = htmlrefdir
     elif htmlrefdir == ''
diff --git a/examples/meson.build b/examples/meson.build
index 501f196..d6efd8b 100644
--- a/examples/meson.build
+++ b/examples/meson.build
@@ -1,6 +1,6 @@
 # examples
 
-# input: sigcxx_dep, build_examples
+# input: sigcxx_own_dep, build_examples
 
 examples = [
 # [[dir-name], exe-name, [sources]]
@@ -21,7 +21,7 @@ foreach ex : examples
 
   exe_file = executable(ex_name, ex_sources,
     cpp_args: '-DSIGCXX_DISABLE_DEPRECATED',
-    dependencies: sigcxx_dep,
+    dependencies: sigcxx_own_dep,
     gui_app: false,
     build_by_default: build_examples
   )
diff --git a/meson.build b/meson.build
index b31ac07..7eb97aa 100644
--- a/meson.build
+++ b/meson.build
@@ -7,7 +7,8 @@ project('libsigc++', 'cpp',
     'cpp_std=c++11',
     'warning_level=0',
   ],
-  meson_version: '>= 0.50.0', # required for python3.path()
+  meson_version: '>= 0.54.0', # required for meson.override_dependency()
+                              # and dep.get_variable(internal:)
 )
 
 sigcxx_api_version = '2.0'
@@ -240,6 +241,19 @@ if not meson.is_subproject()
     project_source_root,
     'untracked' / 'build_scripts',
   )
+else
+  # This is a subproject.
+  sigcxx_dep = declare_dependency(
+    dependencies: sigcxx_own_dep,
+    variables: {
+      'doxytagfile': tag_file.full_path(),
+      'htmlrefdir': install_prefix / install_docdir / 'reference' / 'html',
+      'htmlrefpub': 'http://library.gnome.org/devel/libsigc++/unstable/'
+    }
+  )
+
+  # A main project that looks for sigcxx_pcname.pc shall find sigcxx_dep.
+  meson.override_dependency(sigcxx_pcname, sigcxx_dep)
 endif
 
 # Print a summary.
diff --git a/sigc++/meson.build b/sigc++/meson.build
index 07212a0..ca453d8 100644
--- a/sigc++/meson.build
+++ b/sigc++/meson.build
@@ -2,7 +2,7 @@
 
 # Input: sigcxx_build_dep, sigcxx_pcname, sigcxx_libversion, sigcxx_api_version,
 #        install_includedir, project_source_root, sigc_res
-# Output: source_h_files, built_h_files, sigcxx_dep, built_files_root,
+# Output: source_h_files, built_h_files, sigcxx_own_dep, built_files_root,
 #         built_h_file_targets
 
 source_cc_files = [
@@ -166,10 +166,11 @@ if maintainer_mode
     source_cc_files, built_cc_file_targets, built_h_file_targets,
     extra_sigc_objects,
     version: sigcxx_libversion,
+    darwin_versions: darwin_versions,
     cpp_args: extra_sigc_cppflags,
+    implicit_include_directories: false,
     include_directories: extra_include_dirs,
     dependencies: sigcxx_build_dep,
-    darwin_versions: darwin_versions,
     install: true,
   )
 
@@ -210,10 +211,11 @@ else # not maintainer_mode
     source_cc_files, untracked_built_cc_files,
     extra_sigc_objects,
     version: sigcxx_libversion,
+    darwin_versions: darwin_versions,
     cpp_args: extra_sigc_cppflags,
+    implicit_include_directories: false,
     include_directories: extra_include_dirs,
     dependencies: sigcxx_build_dep,
-    darwin_versions: darwin_versions,
     install: true,
   )
 
@@ -240,9 +242,9 @@ if not meson.is_subproject()
   )
 endif
 
-# This is useful in the main project when libsigc++ is used as a subproject.
-# It's also used when building example programs and test programs.
-sigcxx_dep = declare_dependency(
+# This is used when building example programs and test programs.
+# It's also a part of sigcxx_dep, when libsigc++ is a subproject.
+sigcxx_own_dep = declare_dependency(
   sources: built_h_file_targets,
   link_with: sigcxx_library,
   include_directories: extra_include_dirs,
diff --git a/subprojects/mm-common.wrap b/subprojects/mm-common.wrap
new file mode 100644
index 0000000..296109f
--- /dev/null
+++ b/subprojects/mm-common.wrap
@@ -0,0 +1,9 @@
+[wrap-git]
+directory=mm-common
+url=https://gitlab.gnome.org/GNOME/mm-common.git
+revision=master
+depth=1
+
+[provide]
+dependency_names = mm-common-libstdc++
+program_names = mm-common-get
diff --git a/tests/meson.build b/tests/meson.build
index ca5c318..5bdb407 100644
--- a/tests/meson.build
+++ b/tests/meson.build
@@ -1,6 +1,6 @@
 # tests
 
-# input: sigcxx_dep, do_benchmark, can_benchmark, benchmark_dep
+# input: sigcxx_own_dep, do_benchmark, can_benchmark, benchmark_dep
 
 benchmark_timeout = 100
 
@@ -57,7 +57,7 @@ foreach ex : test_programs
   endforeach
 
   exe_file = executable(ex_name, ex_sources,
-    dependencies: sigcxx_dep,
+    dependencies: sigcxx_own_dep,
     gui_app: false,
     build_by_default: true
   )
@@ -78,7 +78,7 @@ if can_benchmark
     endforeach
 
     exe_file = executable(ex_name, ex_sources,
-      dependencies: [sigcxx_dep, benchmark_dep],
+      dependencies: [sigcxx_own_dep, benchmark_dep],
       gui_app: false,
       build_by_default: do_benchmark
     )