build: featurize docs; always install licenses

doc/meson.build

@@ -1,27 +1,33 @@
 
-if install_docs
-    rst2html_variants = []
+if angle_enabled
+    bindist_deps += custom_target('LICENSE.ANGLE',
+        command : [eolconv_command, host_eol_style, '@INPUT@', '@OUTPUT@'],
+        input : 'LICENSE.ANGLE',
+        output : 'LICENSE.txt',
+        install : true,
+        install_dir : angle_install_path
+    )
+endif
 
-    # This is *completely* ridiculous, but apparently this thing has THAT many faces.
-    basenames = ['rst2html5', 'rst2html', 'rst2html4']
-    suffixes = ['', '-3', '3', '-docutils']
+rst2html_variants = []
 
-    foreach basename : basenames
-        foreach suffix : suffixes
-            variant = '@0@@1@'.format(basename, suffix)
-            rst2html_variants += [variant, '@0@.py'.format(variant)]
-        endforeach
-    endforeach
+# This is *completely* ridiculous, but apparently this thing has THAT many faces.
+basenames = ['rst2html5', 'rst2html', 'rst2html4']
+suffixes = ['', '-3', '3', '-docutils']
 
-    rst2html5 = find_program(
-        rst2html_variants,
-        required : false
-    )
+foreach basename : basenames
+    foreach suffix : suffixes
+        variant = '@0@@1@'.format(basename, suffix)
+        rst2html_variants += [variant, '@0@.py'.format(variant)]
+    endforeach
+endforeach
 
-    if not rst2html5.found()
-        error('rst2html5 from docutils is required to build documentation. Please install it, or disable the `docs` option if you don\'t want it.')
-    endif
+rst2html5 = find_program(
+    rst2html_variants,
+    required : get_option('docs')
+)
 
+if rst2html5.found()
     rst_to_html = generator(rst2html5,
         arguments : [
             '--no-datestamp',
@@ -67,14 +73,4 @@ if install_docs
             depend_files : files('taisei.css')
         )
     endforeach
-
-    if angle_enabled
-        bindist_deps += custom_target('LICENSE.ANGLE',
-            command : [eolconv_command, host_eol_style, '@INPUT@', '@OUTPUT@'],
-            input : 'LICENSE.ANGLE',
-            output : 'LICENSE.txt',
-            install : true,
-            install_dir : angle_install_path
-        )
-    endif
 endif

meson.build

@@ -405,22 +405,16 @@ config.set('TAISEI_BUILDCONF_LOG_FATAL_MSGBOX', (
 ))
 config.set('TAISEI_BUILDCONF_DEBUG_OPENGL', get_option('debug_opengl'))
 
-install_docs = get_option('docs') and host_machine.system() != 'emscripten'
-
 if host_machine.system() == 'windows'
-    if install_docs
-        custom_target('COPYING.txt',
-            command : [eolconv_command, host_eol_style, '@INPUT@', '@OUTPUT@'],
-            input : 'COPYING',
-            output : 'COPYING.txt',
-            install : true,
-            install_dir : doc_path
-        )
-    endif
+    custom_target('COPYING.txt',
+        command : [eolconv_command, host_eol_style, '@INPUT@', '@OUTPUT@'],
+        input : 'COPYING',
+        output : 'COPYING.txt',
+        install : true,
+        install_dir : doc_path
+    )
 else
-    if install_docs
-        install_data('COPYING', install_dir : doc_path)
-    endif
+    install_data('COPYING', install_dir : doc_path)
 endif
 
 if angle_enabled
@@ -439,7 +433,7 @@ if angle_enabled
     endif
 
     # Where to install the libs (prefix-relative)
-    # Also used in docs/meson.build to install the license
+    # Also used in doc/meson.build to install the license
     angle_install_path = join_paths(lib_path, angle_dir)
 
     # Where the game should look (either absolute or SDL_GetBasePath()-relative, depending on configuration)

meson_options.txt

@@ -108,9 +108,9 @@ option(
 
 option(
     'docs',
-    type : 'boolean',
-    value : true,
-    description : 'Build and install documentation'
+    type : 'feature',
+    deprecated : {'true' : 'enabled', 'false' : 'disabled'},
+    description : 'Build and install documentation (requires docutils)'
 )
 
 option(