A few Fedora fixes.

backends.py

@@ -834,8 +834,11 @@ class NinjaBackend(Backend):
         default = 'default all\n\n'
         outfile.write(default)
 
+        ninja_command = environment.detect_ninja()
+        if ninja_command is None:
+            raise RuntimeError('Could not detect ninja command')
         elem = NinjaBuildElement('clean', 'CUSTOM_COMMAND', '')
-        elem.add_item('COMMAND', ['ninja', '-t', 'clean'])
+        elem.add_item('COMMAND', [ninja_command, '-t', 'clean'])
         elem.add_item('description', 'Cleaning')
         if self.environment.coredata.coverage:
             self.generate_gcov_clean(outfile)

environment.py

@@ -532,6 +532,26 @@ def is_osx():
 def is_windows():
     return platform.system().lower() == 'windows'
 
+def is_debianlike():
+    try:
+        open('/etc/debian_version', 'r')
+        return True
+    except FileNotFoundError:
+        return False
+
+def detect_ninja():
+    for n in ['ninja', 'ninja-build']:
+        # Plain 'ninja' or 'ninja -h' yields an error
+        # code. Thanks a bunch, guys.
+        try:
+            p = subprocess.Popen([n, '-t', 'list'], stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
+        except FileNotFoundError:
+            continue
+        p.communicate()
+        if p.returncode == 0:
+            return n
+
+
 header_suffixes = ['h', 'hh', 'hpp', 'hxx', 'H']
 cpp_suffixes = ['cc', 'cpp', 'cxx', 'hh', 'hpp', 'hxx']
 c_suffixes = ['c']

run_tests.py

@@ -23,9 +23,12 @@ install_dir = os.path.join(os.path.split(os.path.abspath(__file__))[0], 'install
 meson_command = './meson.py'
 if True: # Currently we have only one backend.
     backend_flags = []
-    compile_commands = ['ninja']
-    test_commands = ['ninja', 'test']
-    install_commands = ['ninja', 'install']
+    ninja_command = environment.detect_ninja()
+    if ninja_command is None:
+        raise RuntimeError('Could not find Ninja executable.')
+    compile_commands = [ninja_command]
+    test_commands = [ninja_command, 'test']
+    install_commands = [ninja_command, 'install']
 
 def run_test(testdir):
     shutil.rmtree(test_build_dir)