[gimp/wip/jtojnar/tagged-vcs-build] meson: Allow building from non-dist, non-git tagged snapshots

[Jan Tojnar <jtojnar src gnome org>]

commit 8598f2acba7acfc4992fc1f86ade9a985c2c3677
Author: Jan Tojnar <jtojnar gmail com>
Date:   Thu Nov 21 14:16:13 2019 +0100

    meson: Allow building from non-dist, non-git tagged snapshots
    
    8b5060349a95ca552cc1afa9f9c6f4becc2fe7f6 fixed the build from VCS tarballs
    but considers building them unsupported due to being unable to pinpoint
    the corresponding Git commit. This is not an issue with tagged commits,
    since they will have even patch component of the version.
    
    Let's fallback version.h to meson.project_version() in those cases.

 meson.build | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)
---
diff --git a/meson.build b/meson.build
index f295c43e7c..a8ffce0f06 100644
--- a/meson.build
+++ b/meson.build
@@ -65,6 +65,7 @@ conf.set_quoted('GETTEXT_PACKAGE', gettext_package)
 conf.set_quoted('GIMP_VERSION', gimp_version)
 
 stable = (gimp_app_version_minor % 2 == 0)
+tagged = (gimp_app_version_micro % 2 == 0)
 conf.set10('GIMP_UNSTABLE', not stable)
 
 versionconfig = configuration_data()
@@ -1442,23 +1443,23 @@ if is_git_repository or not has_version_h
     output: 'git-version.h.in.1',
     command: [ git, 'describe', '--always', ],
     replace_string: '@GIMP_GIT_VERSION@',
-    fallback: 'unknown (unsupported)',
+    fallback: tagged ? meson.project_version() : 'unknown (unsupported)',
   )
   gitversion_h2 = vcs_tag(
     input : gitversion_h1,
     output: 'git-version.h.in.2',
     command: [ git, 'rev-parse', '--short', 'HEAD', ],
     replace_string: '@GIMP_GIT_VERSION_ABBREV@',
-    fallback: 'unknown (unsupported)',
+    fallback: tagged ? meson.project_version() : 'unknown (unsupported)',
   )
   gitversion_h = vcs_tag(
     input : gitversion_h2,
     output: 'git-version.h',
     command: [ git, 'log', '-n1', '--date=format:%Y', '--pretty=%cd', ],
     replace_string: '@GIMP_GIT_LAST_COMMIT_YEAR@',
-    fallback: 'unknown (unsupported)',
+    fallback: tagged ? meson.project_version() : 'unknown (unsupported)',
   )
-  if not is_git_repository or not git.found()
+  if (not is_git_repository or not git.found()) and not tagged
   # We create git-version.h but know it will be useless because we are
   # not in a git repository. Output a warning.
   git_warning = '''