Meson build: Set default value of the 'warnings' option to 'min'

* MSVC_NMake/meson.build: Copy sigc++config.h with configure_file().
* Makefile.am: Remove tools/dist-cmd.py.
* docs/docs/manual/meson.build:
* docs/docs/reference/meson.build: Don't use tools/dist-cmd.py.
* meson.build: Use dist-warnings when a tarball is tested by
'ninja dist' or 'meson dist'. Check if doc-reference.py exists, if not
maintainer-mode.
* meson_options.txt: Set default value of the 'warnings' to 'min'.
Add 'dist-warnings' with default value 'fatal'.
* tools/dist-cmd.py: Removed file. It's not necessary in add_dist_script()
when the first parameter is python3.path().

7 files changed, 40 insertions, 34 deletions

diff --git a/MSVC_NMake/meson.build b/MSVC_NMake/meson.build
index a799535..da56141 100644
--- a/MSVC_NMake/meson.build
+++ b/MSVC_NMake/meson.build
@@ -1,7 +1,7 @@
 # MSVC_NMake
 
-# Input: pkg_conf_data, project_build_root, python3
-# Output: -
+# Input: pkg_conf_data, sigcxxconfig_h, project_build_root, python3
+# Output: sigc_rc
 
 sigc_rc = configure_file(
   input: 'sigc.rc.in',
@@ -10,11 +10,11 @@ sigc_rc = configure_file(
 )
 
 # Copy the generated configuration header into the MSVC project directory.
-cmd_py = '''
-import shutil
-shutil.copy2("@0@", "@1@")
-'''.format(project_build_root / 'sigc++config.h', project_build_root / 'MSVC_NMake')
-meson.add_postconf_script(python3.path(), '-c', cmd_py)
+configure_file(
+  input: sigcxxconfig_h,
+  output: 'sigc++config.h',
+  copy: true,
+)
 
 untracked_msvc_nmake = 'untracked' / 'MSVC_NMake'
 handle_built_files = project_source_root / 'tools' / 'handle-built-files.py'
@@ -24,10 +24,10 @@ if not meson.is_subproject()
   # (add_dist_script() is not allowed in a subproject)
 
   meson.add_dist_script(
-    python3.path(), dist_cmd,
     python3.path(), handle_built_files, 'dist_gen_msvc_files',
     meson.current_build_dir(),
     untracked_msvc_nmake,
-    project_build_root / 'sigc++config.h', meson.current_build_dir() / 'sigc.rc',
+    project_build_root / 'sigc++config.h',
+    meson.current_build_dir() / 'sigc.rc',
   )
 endif
diff --git a/Makefile.am b/Makefile.am
index 80b4136..0b7b78b 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -55,7 +55,6 @@ EXTRA_DIST = \
   examples/meson.build \
   sigc++/meson.build \
   tests/meson.build \
-  tools/dist-cmd.py \
   tools/handle-built-files.py \
   tools/tutorial-custom-cmd.py \
   untracked/README
diff --git a/docs/docs/manual/meson.build b/docs/docs/manual/meson.build
index c17bf3e..a90bb09 100644
--- a/docs/docs/manual/meson.build
+++ b/docs/docs/manual/meson.build
@@ -1,7 +1,7 @@
 # docs/docs/manual
 
 # input: install_datadir, sigcxx_pcname, tutorial_custom_cmd, python3,
-#        build_documentation, dist_cmd, book_name
+#        build_documentation, book_name
 # output: can_parse_and_validate, build_pdf_by_default, can_build_pdf,
 #         install_tutorialdir
 
@@ -81,7 +81,6 @@ if not meson.is_subproject()
   # Distribute built files.
   # (add_dist_script() is not allowed in a subproject)
   meson.add_dist_script(
-    python3.path(), dist_cmd,
     python3.path(), tutorial_custom_cmd, 'dist_doc',
     doc_dist_dir,
     meson.current_build_dir(),
diff --git a/docs/docs/reference/meson.build b/docs/docs/reference/meson.build
index 98e69a3..464214b 100644
--- a/docs/docs/reference/meson.build
+++ b/docs/docs/reference/meson.build
@@ -2,7 +2,7 @@
 
 # Input: project_build_root, project_source_root, sigcxx_pcname,
 #        sigcxx_api_version, perl, build_documentation, source_h_files,
-#        hg_ccg_basenames, install_datadir, dist_cmd, python3
+#        hg_ccg_basenames, install_datadir, python3, doc_reference
 # Output: install_docdir, install_devhelpdir, book_name
 
 # There are no built source files in libsigc++-3.0.
@@ -115,7 +115,6 @@ if not meson.is_subproject()
   # Distribute built files and files copied by mm-common-get.
   # (add_dist_script() is not allowed in a subproject)
   meson.add_dist_script(
-    python3.path(), dist_cmd,
     python3.path(), doc_reference, 'dist_doc',
     doctool_dir,
     doctool_dist_dir,
diff --git a/meson.build b/meson.build
index 449d43c..2bbb307 100644
--- a/meson.build
+++ b/meson.build
@@ -56,11 +56,22 @@ sys.exit(os.path.isdir("@0@") or os.path.isfile("@0@"))
 '''.format(project_source_root / '.git')
 is_git_build = run_command(python3, '-c', cmd_py).returncode() != 0
 
+# Are we testing a dist tarball while it's being built?
+# There ought to be a better way. https://github.com/mesonbuild/meson/issues/6866
+is_dist_check = project_source_root.contains('dist-unpack') and \
+                project_build_root.contains('dist-build')
+
 # Options.
 maintainer_mode_opt = get_option('maintainer-mode')
 maintainer_mode = maintainer_mode_opt == 'true' or \
                  (maintainer_mode_opt == 'if-git-build' and is_git_build)
-warning_level = get_option('warnings')
+if is_dist_check
+  message('Looks like a tarball is being tested. ' + \
+          'Option "dist-warnings" is used instead of "warnings".')
+  warning_level = get_option('dist-warnings')
+else
+  warning_level = get_option('warnings')
+endif
 build_deprecated_api = get_option('build-deprecated-api')
 build_documentation_opt = get_option('build-documentation')
 build_documentation = build_documentation_opt == 'true' or \
@@ -110,13 +121,23 @@ script_dir = project_source_root / 'untracked' / 'build_scripts'
 doc_reference = script_dir / 'doc-reference.py'
 dist_changelog = script_dir / 'dist-changelog.py'
 dist_build_scripts = script_dir / 'dist-build-scripts.py'
-dist_cmd = project_source_root / 'tools' / 'dist-cmd.py' # Must be committed to git.
 tutorial_custom_cmd = project_source_root / 'tools' / 'tutorial-custom-cmd.py'
 
-if maintainer_mode and mm_common_get.found()
+if maintainer_mode
   # Copy files to untracked/build_scripts and untracked/docs/docs.
   run_command(mm_common_get, '--force', script_dir,
     project_source_root / 'untracked' / 'docs' / 'docs')
+else
+  cmd_py = '''
+import os
+import sys
+sys.exit(os.path.isfile("@0@"))
+'''.format(doc_reference)
+  file_exists = run_command(python3, '-c', cmd_py).returncode() != 0
+  if not file_exists
+    warning('Missing files in untracked/. ' + \
+    'Enable maintainer-mode if you want to build documentation or create a dist tarball.')
+  endif
 endif
 
 # Set compiler warnings.
@@ -187,7 +208,7 @@ configure_file(
 )
 
 install_includeconfigdir = install_libdir / sigcxx_pcname / 'include'
-configure_file(
+sigcxxconfig_h = configure_file(
   input: 'sigc++config.h.meson',
   output: 'sigc++config.h',
   configuration: pkg_conf_data,
@@ -206,14 +227,12 @@ if not meson.is_subproject()
   # Add a ChangeLog file to the distribution directory.
   # (add_dist_script() is not allowed in a subproject)
   meson.add_dist_script(
-    python3.path(), dist_cmd,
     python3.path(), dist_changelog,
     project_source_root,
   )
   # Add build scripts to the distribution directory, and delete .gitignore
   # files and an empty $MESON_DIST_ROOT/build/ directory.
   meson.add_dist_script(
-    python3.path(), dist_cmd,
     python3.path(), dist_build_scripts,
     project_source_root,
     'untracked' / 'build_scripts',
diff --git a/meson_options.txt b/meson_options.txt
index b1ffd54..138e302 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -1,7 +1,9 @@
 option('maintainer-mode', type: 'combo', choices: ['false', 'if-git-build', 'true'],
-  value: 'if-git-build', description: 'Generate source code from .hg and .ccg files')
+  value: 'if-git-build', description: 'Let mm-common-get copy some files to untracked/')
 option('warnings', type: 'combo', choices: ['no', 'min', 'max', 'fatal'],
-  value: 'fatal', description: 'Compiler warning level')
+  value: 'min', description: 'Compiler warning level')
+option('dist-warnings', type: 'combo', choices: ['no', 'min', 'max', 'fatal'],
+  value: 'fatal', description: 'Compiler warning level when a tarball is created')
 option('build-deprecated-api', type: 'boolean', value: true,
   description: 'Build deprecated API and include it in the library')
 option('build-documentation', type: 'combo', choices: ['false', 'if-maintainer-mode', 'true'],
diff --git a/tools/dist-cmd.py b/tools/dist-cmd.py
deleted file mode 100755
index 30da5da..0000000
--- a/tools/dist-cmd.py
+++ /dev/null
@@ -1,12 +0,0 @@
-#!/usr/bin/env python3
-
-# External command, intended to be called with meson.add_dist_script() in meson.build.
-# meson.add_dist_script() can't call a script that's not committed to git.
-# This script shall be committed. It can be used for calling other non-committed scripts.
-
-# dist-cmd.py <cmd> <args>...
-
-import sys
-import subprocess
-
-sys.exit(subprocess.run(sys.argv[1:]).returncode)