meson: generate articles

While the Meson build system already knows to generate man pages and our
user manual, it does not yet generate the random assortment of articles
that we have. Plug this gap.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/howto/meson.build

@@ -0,0 +1,62 @@
+howto_sources = [
+  'coordinate-embargoed-releases.txt',
+  'keep-canonical-history-correct.txt',
+  'maintain-git.txt',
+  'new-command.txt',
+  'rebase-from-internal-branch.txt',
+  'rebuild-from-update-hook.txt',
+  'recover-corrupted-blob-object.txt',
+  'recover-corrupted-object-harder.txt',
+  'revert-a-faulty-merge.txt',
+  'revert-branch-rebase.txt',
+  'separating-topic-branches.txt',
+  'setup-git-server-over-http.txt',
+  'update-hook-example.txt',
+  'use-git-daemon.txt',
+  'using-merge-subtree.txt',
+  'using-signed-tag-in-pull-request.txt',
+]
+
+howto_index = custom_target(
+  command: [
+    shell,
+    meson.current_source_dir() / 'howto-index.sh',
+    '@INPUT@',
+  ],
+  env: script_environment,
+  capture: true,
+  input: howto_sources,
+  output: 'howto-index.txt',
+)
+
+custom_target(
+  command: asciidoc_html_options,
+  input: howto_index,
+  output: 'howto-index.html',
+  depends: documentation_deps,
+  install: true,
+  install_dir: get_option('datadir') / 'doc/git-doc',
+)
+
+foreach howto : howto_sources
+  howto_stripped = custom_target(
+    command: [
+      find_program('sed'),
+      '-e',
+      '1,/^$/d',
+      '@INPUT@',
+    ],
+    input: howto,
+    output: fs.stem(howto) + '.stripped',
+    capture: true,
+  )
+
+  custom_target(
+    command: asciidoc_html_options,
+    input: howto_stripped,
+    output: fs.stem(howto_stripped.full_path()) + '.html',
+    depends: documentation_deps,
+    install: true,
+    install_dir: get_option('datadir') / 'doc/git-doc/howto',
+  )
+endforeach