vcs_tag: handle non-str / non-file arguments

This makes vcs_tag behave like other commands so it accepts not only
string and file arguments, but also exe, custom_tgt, and
external_program.

docs/yaml/functions/vcs_tag.yaml

@@ -22,7 +22,7 @@ description: |
 
 kwargs:
   command:
-    type: list[str | file]
+    type: list[exe | external_program | custom_tgt | file | str]
     description: |
       The command to execute, see [[custom_target]] for details
       on how this command must be specified.
@@ -32,6 +32,8 @@ kwargs:
 
       *(since 0.62.0)* [[@file]] is accepted.
 
+      *(since 0.63.0)* [[@custom_tgt]], [[@exe]], and [[@external_program]] are accepted.
+
   input:
     type: str
     required: true

mesonbuild/interpreter/interpreter.py

@@ -1752,11 +1752,14 @@ external dependencies (including libraries) must go to "dependencies".''')
         vcs_cmd = kwargs['command']
         source_dir = os.path.normpath(os.path.join(self.environment.get_source_dir(), self.subdir))
         if vcs_cmd:
-            if isinstance(vcs_cmd[0], mesonlib.File):
-                FeatureNew.single_use('vcs_tag with file as the first argument', '0.62.0', self.subproject, location=node)
-            maincmd = self.find_program_impl(vcs_cmd[0], required=False)
-            if maincmd.found():
-                vcs_cmd[0] = maincmd
+            if isinstance(vcs_cmd[0], (str, mesonlib.File)):
+                if isinstance(vcs_cmd[0], mesonlib.File):
+                    FeatureNew.single_use('vcs_tag with file as the first argument', '0.62.0', self.subproject, location=node)
+                maincmd = self.find_program_impl(vcs_cmd[0], required=False)
+                if maincmd.found():
+                    vcs_cmd[0] = maincmd
+            else:
+                FeatureNew.single_use('vcs_tag with custom_tgt, external_program, or exe as the first argument', '0.63.0', self.subproject, location=node)
         else:
             vcs = mesonlib.detect_vcs(source_dir)
             if vcs:

test cases/common/66 vcstag/meson.build

@@ -17,12 +17,26 @@ fallback : '1.0.0')
 version_src_fallback = vcs_tag(input : 'vcstag.c.in',
 output : 'vcstag-fallback.c')
 
+git = find_program('git')
+
+version_src_git_program = vcs_tag(input : 'vcstag.c.in',
+output : 'vcstag-git-program.c',
+command : [git, 'rev-parse', 'HEAD'],
+fallback : '1.0.0')
+
 version_src_file = vcs_tag(input : 'vcstag.c.in',
 output : 'vcstag-file.c',
 command : files('version.py'))
 
-executable('tagprog', 'tagprog.c', version_src)
+tagprog = executable('tagprog', 'tagprog.c', version_src)
+
+version_src_executable = vcs_tag(input : 'vcstag.c.in',
+output : 'vcstag-executable.c',
+command : [tagprog])
+
 executable('tagprog-custom', 'tagprog.c', version_src_custom)
 executable('tagprog-fallback', 'tagprog.c', version_src_fallback)
 executable('tagprog-notfound-fallback', 'tagprog.c', version_src_notfound_fallback)
+executable('tagprog-git-program', 'tagprog.c', version_src_git_program)
+executable('tagprog-executable', 'tagprog.c', version_src_executable)
 executable('tagprog-file', 'tagprog.c', version_src_file)