[gtkmm-documentation] CI: Run ninja install

[Kjell Ahlstedt <kjellahl src gnome org>]

commit a2334ed0b3bddb5b7da8e77c3be4d11aac75d4a7
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Fri Aug 20 19:13:15 2021 +0200

    CI: Run ninja install
    
    Translations are built only when the tutorial is installed.
    All documentation files are copied to one directory when the
    tutorial is installed, making it easy to move all necessary files
    to the public/ directory.

 .gitlab-ci.yml | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 20ba2d7..0c4404b 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -9,9 +9,6 @@ stages:
     - export PATH="$HOME/.local/bin:$PATH"
     - dnf install -y ${FEDORA_DEPS}
     - pip install --user meson==${MESON_VERSION}
-  script:
-    - meson setup ${MESON_OPTIONS} _build .
-    - ninja -C _build
 
 docs-validation:
   extends: .build-default
@@ -30,6 +27,12 @@ docs-validation:
       python3-wheel
     MESON_VERSION: "0.50.0"
     MESON_OPTIONS: "-Dbuild-examples=false -Dvalidation=true -Dbuild-translations=true -Dbuild-pdf=false"
+  script:
+    - meson setup ${MESON_OPTIONS} _build .
+    - ninja -C _build
+    # Translations are built on installation as long as issue
+    # https://github.com/mesonbuild/meson/issues/2775 has not been fixed.
+    - ninja -C _build install
 
 html-tutorial:
   extends: .build-default
@@ -45,17 +48,24 @@ html-tutorial:
       python3-wheel
     MESON_VERSION: "0.50.0"
     MESON_OPTIONS: "-Dbuild-examples=false -Dvalidation=false -Dbuild-translations=false -Dbuild-pdf=false"
+  script:
+    - meson setup --prefix=/usr --datadir=share ${MESON_OPTIONS} _build .
+    - ninja -C _build
+    # Installation copies all documentation files to one directory.
+    - ninja -C _build install
+    - mkdir -p _build/docs/installed-tutorial
+    - mv /usr/share/doc/gtkmm-4.0/tutorial/html _build/docs/installed-tutorial
   artifacts:
     when: always
     paths:
-      - _build/docs/tutorial
+      - _build/docs/installed-tutorial
 
 pages:
   stage: deploy
   needs: ["html-tutorial"]
   script:
     - mkdir public
-    - mv _build/docs/tutorial public
+    - mv _build/docs/installed-tutorial/html/* public
   artifacts:
     paths:
       - public