build: Move xdgmime to a meson subproject

This means:
 - It’s always available, so the tests no longer have to be optional
 - It gets bundled in release tarballs so the above is always true
 - The `meson setup` and `meson build` commands will automatically
   update it if needed
 - It gets built using meson, rather than autotools, so the old
   GNU make build system in xdgmime can be dropped (see
   https://gitlab.freedesktop.org/xdg/xdgmime/-/issues/36)
 - The `xdgmime-path` meson option is no longer needed and has been
   dropped

Signed-off-by: Philip Withnall <pwithnall@gnome.org>

9 files changed, 59 insertions, 66 deletions

diff --git a/.gitignore b/.gitignore
index a060999..dcd6db0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
 /_build/
 /.python-version
+/subprojects/*/
\ No newline at end of file
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 05b8cb8..b1aa762 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -70,7 +70,7 @@ variables:
     FDO_DISTRIBUTION_TAG: "2022-08-15.0"
     BUILD_OS: fedora
     FDO_DISTRIBUTION_VERSION: 38
-    FDO_DISTRIBUTION_PACKAGES: "gcc gcc-c++ glibc-devel make libxml2-devel glib2-devel gettext git xmlto findutils gettext-devel meson"
+    FDO_DISTRIBUTION_PACKAGES: "gcc gcc-c++ glibc-devel libxml2-devel glib2-devel gettext git xmlto findutils gettext-devel meson"
   
 .fedora-x86_64:
   extends:
@@ -100,9 +100,6 @@ fedora-x86_64-container_prep:
 .do-build:
   stage: "Build and test"
   script:
-    # Compile xdgmime
-    - make -C xdgmime
-
     # Compile and test shared-mime-info
     - meson setup _build
     - meson compile -C _build
diff --git a/.gitmodules b/.gitmodules
index c13ff7a..dc83889 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,4 @@
-[submodule "xdgmime"]
-	path = xdgmime
+[submodule "subprojects/xdgmime"]
+	path = subprojects/xdgmime
 	url = https://gitlab.freedesktop.org/xdg/xdgmime.git
+	shallow = true
diff --git a/HACKING.md b/HACKING.md
index 51464f7..5b6d9f3 100644
--- a/HACKING.md
+++ b/HACKING.md
@@ -35,20 +35,21 @@ more test files to be added to the test suite.
 Test suite
 ----------
 
-You need to have xdgmime [1] checked out and compiled before you configure
-and build shared-mime-info. In the shared-mime-info git repository, getting
-xdgmime is taken care of by using a git submodule; run `git submodule update
---init` after cloning the shared-mime-info repo. If you wish to keep the
-submodule automatically up to date on pull, `git config submodule.recurse
-true` in the shared-mime-info dir helps with that. To build xdgmime, `cd
-xdgmime/src && make` (ignore the Meson build system).
-
-By default, the build system will expect the xdgmime directory to be in the
-shared-mime-info directory. `./xdgmime/src/test-mime-data` is run against
-`tests/mime-detection/list`. An alternate path to xdgmime can be passed by
-using the `xdgmime-path` meson option such as `-Dxdgmime-path=/path/to/xdgmime`.
-
-The format of the file is:
+The shared-mime-info tests depend on xdgmime [1]. This is taken care of as a
+git submodule and as a meson subproject. Run `meson subprojects update` or
+`git submodule update --init` after cloning the shared-mime-info repo. If you
+wish to keep the submodule automatically up to date on pull,
+`git config submodule.recurse true` in the shared-mime-info dir helps with that.
+
+xdgmime will be built automatically by the meson build system for
+shared-mime-info.
+
+Meson’s subprojects system[2] requires the xdgmime directory to be in
+`subprojects/xdgmime`. An alternate path to xdgmime can be configured by
+installing a pkg-config file for xdgmime which points to the desired location.
+
+As part of the tests, `./xdgmime/src/test-mime-data` is run against
+`tests/mime-detection/list`. The format of the file is:
 `<testcase filename> <expected mime-type> <expected failures>`
 
 The expected failures is whether matching the file with the mime-type would
@@ -62,6 +63,7 @@ test files in the `staging-tests/` sub-directory.
 
 [1]: Repository details at:
 https://gitlab.freedesktop.org/xdg/xdgmime
+[2]: https://mesonbuild.com/Subprojects.html
 
 Releasing
 ---------
diff --git a/meson.build b/meson.build
index 93acd40..1f067a4 100644
--- a/meson.build
+++ b/meson.build
@@ -26,26 +26,16 @@ xmllint = find_program('xmllint')
 xmlto   = find_program('xmlto', required: false)
 
 ###############################################################################
-# Find xdgmime
+# Find xdgmime. It needs to be a native dependency (i.e. compiled for the build
+# system rather than the host system) so we can run its programs as part of the
+# shared-mime-info build.
 
-xdgmime = get_option('xdgmime-path') / 'src'
+subproject('xdgmime')
+xdgmime_dep = dependency('xdgmime', native: true)
 
-xdgmime_print_mime_data = find_program(xdgmime/'print-mime-data', required: false)
-xdgmime_test_mime_data  = find_program(xdgmime/'test-mime-data', required: false)
-xdgmime_test_mime       = find_program(xdgmime/'test-mime', required: false)
-xdgmime_found = (
-    xdgmime_print_mime_data.found() and
-    xdgmime_test_mime_data.found()  and
-    xdgmime_test_mime.found()
-)
-
-if not xdgmime_found
-    warning('''
-***************************************************************************
-*** xdgmime not compiled, test suite cannot run. Check HACKING for info ***
-***************************************************************************
-    ''')
-endif
+xdgmime_print_mime_data = find_program('print-mime-data')
+xdgmime_test_mime_data  = find_program('test-mime-data')
+xdgmime_test_mime       = find_program('test-mime')
 
 ###############################################################################
 # Check if GCC needs -lstdc++fs (before 9.1)
diff --git a/meson_options.txt b/meson_options.txt
index c5b7e5d..7f9c20c 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -14,7 +14,3 @@ option('build-translations', type: 'boolean', value: true,
 option('build-tests', type: 'boolean', value: true,
     description: 'Build the test suite.  If not set then there will be no \'test\' build target.',
 )
-
-option('xdgmime-path', type: 'string', value: './xdgmime',
-    description: 'Path to the xdgmime executable',
-)
diff --git a/subprojects/xdgmime.wrap b/subprojects/xdgmime.wrap
new file mode 100644
index 0000000..8e3a745
--- /dev/null
+++ b/subprojects/xdgmime.wrap
@@ -0,0 +1,8 @@
+[wrap-git]
+directory=xdgmime
+url=https://gitlab.freedesktop.org/xdg/xdgmime.git
+revision=master
+depth=1
+
+[provide]
+dependency_names = xdgmime
\ No newline at end of file
diff --git a/tests/meson.build b/tests/meson.build
index a073abe..8f0e069 100644
--- a/tests/meson.build
+++ b/tests/meson.build
@@ -2,31 +2,29 @@ if meson.is_cross_build()
     subdir_done()
 endif
 
-if xdgmime_found
-    test('test-staging',
-         find_program('test_staging.sh'),
-         args: [
-             meson.source_root(),
-             meson.build_root(),
-             freedesktop_org_xml,
-             update_mime_database,
-             xdgmime_print_mime_data.path(),
-         ]
-    )
+test('test-staging',
+    find_program('test_staging.sh'),
+    args: [
+        meson.source_root(),
+        meson.build_root(),
+        freedesktop_org_xml,
+        update_mime_database,
+        xdgmime_print_mime_data.path(),
+    ]
+)
 
-    test('test-mime',
-        find_program('test_mime.sh'),
-        args: [
-            meson.source_root(),
-            meson.build_root(),
-            freedesktop_org_xml,
-            update_mime_database,
-            xdgmime_test_mime_data.path(),
-            xdgmime_test_mime.path(),
-            test_tree_magic.full_path(),
-        ],
-    )
-endif
+test('test-mime',
+    find_program('test_mime.sh'),
+    args: [
+        meson.source_root(),
+        meson.build_root(),
+        freedesktop_org_xml,
+        update_mime_database,
+        xdgmime_test_mime_data.path(),
+        xdgmime_test_mime.path(),
+        test_tree_magic.full_path(),
+    ],
+)
 
 run_target('check-generic-icons',
     command: [ find_program('test_generic_icons.sh'), freedesktop_org_xml ],
diff --git a/xdgmime b/xdgmime
deleted file mode 160000
-Subproject 179296748e92bd91bf531656632a1056307fb7b