Implement mlog.warning and use it everywhere for warnings

Prepends the string with 'WARNING:' in ANSI yellow.

Closes https://github.com/mesonbuild/meson/issues/961

2 files changed, 4 insertions, 4 deletions

diff --git a/mesonbuild/backend/backends.py b/mesonbuild/backend/backends.py
index a4f2b51..bd75fdb 100644
--- a/mesonbuild/backend/backends.py
+++ b/mesonbuild/backend/backends.py
@@ -81,8 +81,8 @@ class Backend():
     def get_target_filename(self, t):
         if isinstance(t, build.CustomTarget):
             if len(t.get_outputs()) != 1:
-                mlog.log(mlog.red('WARNING'), 'custom_target {!r} has more ' \
-                         'than one output! Using the first one.'.format(t.name))
+                mlog.warning('custom_target {!r} has more than one output! ' \
+                             'Using the first one.'.format(t.name))
             filename = t.get_outputs()[0]
         else:
             assert(isinstance(t, build.BuildTarget))
diff --git a/mesonbuild/backend/ninjabackend.py b/mesonbuild/backend/ninjabackend.py
index 0f8dcae..63380bd 100644
--- a/mesonbuild/backend/ninjabackend.py
+++ b/mesonbuild/backend/ninjabackend.py
@@ -215,7 +215,7 @@ int dummy;
             with open(os.path.join(builddir, 'compile_commands.json'), 'wb') as f:
                 f.write(jsondb)
         except Exception:
-            mlog.log(mlog.red('Warning:', 'Could not create compilation database.'))
+            mlog.warning('Could not create compilation database.')
 
     # Get all generated headers. Any source file might need them so
     # we need to add an order dependency to them.
@@ -581,7 +581,7 @@ int dummy;
             elem.add_item('DESC', 'Generating HTML coverage report.')
             elem.write(outfile)
         if not added_rule:
-            mlog.log(mlog.red('Warning:'), 'coverage requested but neither gcovr nor lcov/genhtml found.')
+            mlog.warning('coverage requested but neither gcovr nor lcov/genhtml found.')
 
     def generate_install(self, outfile):
         install_data_file = os.path.join(self.environment.get_scratch_dir(), 'install.dat')