Fix i18n target name when using @BASENAME@ and configure_file() input

Fixes: #9022

mesonbuild/modules/i18n.py

@@ -108,18 +108,15 @@ class I18nModule(ExtensionModule):
 
         kwargs['command'] = command
 
-        inputfile = kwargs['input']
-        # I have no idea why/how this if isinstance(inputfile, mesonlib.HoldableObject) works / used to work...
-        if isinstance(inputfile, mesonlib.HoldableObject):
-            ct = build.CustomTarget(kwargs['output'] + '_merge', state.subdir, state.subproject, kwargs)
-        else:
-            if isinstance(inputfile, list):
-                # We only use this input file to create a name of the custom target.
-                # Thus we can ignore the other entries.
-                inputfile = inputfile[0]
-            if isinstance(inputfile, str):
-                inputfile = mesonlib.File.from_source_file(state.environment.source_dir,
-                                                           state.subdir, inputfile)
+        # We only use this input file to create a name of the custom target.
+        # Thus we can ignore the other entries.
+        inputfile = mesonlib.extract_as_list(kwargs, 'input')[0]
+        if isinstance(inputfile, str):
+            inputfile = mesonlib.File.from_source_file(state.environment.source_dir,
+                                                       state.subdir, inputfile)
+        if isinstance(inputfile, mesonlib.File):
+            # output could be '@BASENAME@' in which case we need to do substitutions
+            # to get a unique target name.
             output = kwargs['output']
             ifile_abs = inputfile.absolute_path(state.environment.source_dir,
                                                 state.environment.build_dir)
@@ -127,6 +124,9 @@ class I18nModule(ExtensionModule):
             outputs = mesonlib.substitute_values([output], values)
             output = outputs[0]
             ct = build.CustomTarget(output + '_' + state.subdir.replace('/', '@').replace('\\', '@') + '_merge', state.subdir, state.subproject, kwargs)
+        else:
+            ct = build.CustomTarget(kwargs['output'] + '_merge', state.subdir, state.subproject, kwargs)
+
         return ModuleReturnValue(ct, [ct])
 
     @FeatureNewKwargs('i18n.gettext', '0.37.0', ['preset'])

test cases/frameworks/6 gettext/data/meson.build

@@ -27,4 +27,32 @@ i18n.merge_file(
   install_dir: join_paths(get_option('datadir'), 'applications')
 )
 
+# Regression test when passing File object as input and '@BASENAME@' as output
+# in multiple i18n.merge_file() calls. It used to make target name collision.
+# https://github.com/mesonbuild/meson/issues/9022
+i18n.merge_file(
+  input: configure_file(
+    input: 'test5.desktop.in.in',
+    output: '@BASENAME@',
+    configuration: { 'NAME': 'Application' },
+  ),
+  output: '@BASENAME@',
+  type: 'desktop',
+  po_dir: '../po',
+  install: true,
+  install_dir: join_paths(get_option('datadir'), 'applications')
+)
+i18n.merge_file(
+  input: configure_file(
+    input: 'test6.desktop.in.in',
+    output: '@BASENAME@',
+    configuration: { 'NAME': 'Application' },
+  ),
+  output: '@BASENAME@',
+  type: 'desktop',
+  po_dir: '../po',
+  install: true,
+  install_dir: join_paths(get_option('datadir'), 'applications')
+)
+
 subdir('data3')

test cases/frameworks/6 gettext/data/test5.desktop.in.in

@@ -0,0 +1,6 @@
+[Desktop Entry]
+Name=Test 2
+GenericName=@NAME@
+Comment=Test Application
+Type=Application
+

test cases/frameworks/6 gettext/data/test6.desktop.in.in

@@ -0,0 +1,6 @@
+[Desktop Entry]
+Name=Test 2
+GenericName=@NAME@
+Comment=Test Application
+Type=Application
+

test cases/frameworks/6 gettext/test.json

@@ -9,7 +9,9 @@
     {"type": "file", "file": "usr/share/applications/test.plugin"},
     {"type": "file", "file": "usr/share/applications/test2.desktop"},
     {"type": "file", "file": "usr/share/applications/test3.desktop"},
-    {"type": "file", "file": "usr/share/applications/test4.desktop"}
+    {"type": "file", "file": "usr/share/applications/test4.desktop"},
+    {"type": "file", "file": "usr/share/applications/test5.desktop"},
+    {"type": "file", "file": "usr/share/applications/test6.desktop"}
   ],
   "matrix": {
     "options": {