New test and fixes for -n / --no-exec when using ninja

CHANGES.txt

@@ -85,6 +85,9 @@ RELEASE  VERSION/DATE TO BE FILLED IN LATER
     - Fix typos in preface, Chapter 6, Chapter 9 and Chapter 10 of User Guide
     - Fix broken links in Chapter 1 of User Guide
 
+  From Paul Movall:
+    - Fix --no-exec when using ninja tool
+
   From Keith F. Prussing:
     - Add RequiredPackage to the LaTeX scanner for recursive scanning of
       custom LaTeX packages.

RELEASE.txt

@@ -60,6 +60,8 @@ FIXES
 
 - Fix CPPDEFINES test using pkg-config, which was failing on GH Actions.
 
+- Fix -n / --no-exec support when using ninja tool
+
 IMPROVEMENTS
 ------------
 

SCons/Tool/ninja_tool/__init__.py

@@ -93,7 +93,8 @@ def ninja_builder(env, target, source):
 
     if str(env.get("NINJA_DISABLE_AUTO_RUN")).lower() not in ['1', 'true']:
         num_jobs = env.get('NINJA_MAX_JOBS', env.GetOption("num_jobs"))
-        cmd += ['-j' + str(num_jobs)] + env.get('NINJA_CMD_ARGS', '').split() + NINJA_CMDLINE_TARGETS
+        ninja_default_cmd_args = '-n' if env.GetOption("no_exec") else ''
+        cmd += ['-j' + str(num_jobs)] + env.get('NINJA_CMD_ARGS', ninja_default_cmd_args).split() + NINJA_CMDLINE_TARGETS
         print(f"ninja will be run with command line targets: {' '.join(NINJA_CMDLINE_TARGETS)}")
         print("Executing:", str(' '.join(cmd)))
 

test/ninja/dry_run.py

@@ -0,0 +1,69 @@
+#!/usr/bin/env python
+#
+# Copyright The SCons Foundation
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be included
+# in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
+# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+#
+
+import os
+
+import TestSCons
+from TestCmd import IS_WINDOWS
+
+test = TestSCons.TestSCons()
+
+try:
+    import ninja
+except ImportError:
+    test.skip_test("Could not find module in python")
+
+_python_ = TestSCons._python_
+_exe = TestSCons._exe
+
+ninja_bin = TestSCons.NINJA_BINARY
+
+test.dir_fixture('ninja-fixture')
+
+test.file_fixture('ninja_test_sconscripts/sconstruct_generate_and_build_cxx',
+                  'SConstruct')
+
+# generate simple build
+test.run()
+test.must_contain_all_lines(test.stdout(), ['Generating: build.ninja'])
+test.must_contain_all(test.stdout(), 'Executing:')
+test.must_contain_all(test.stdout(), 'ninja%(_exe)s -f' % locals())
+test.run(program=test.workpath('test2' + _exe), stdout="print_function")
+
+# clean build and ninja files
+test.run(arguments='-c', stdout=None)
+test.must_contain_all_lines(test.stdout(), [
+    'Removed test2.o',
+    'Removed test2',
+    'Removed build.ninja'])
+test.must_not_exist([test.workpath('test2' + _exe), test.workpath('build.ninja')])
+
+# run in no-exec / dry-run mode, which should generate the ninja build files but
+# not execute any portion of the build including ninja
+test.run(arguments='--no-exec', stdout=None)
+test.must_contain_all_lines(test.stdout(), ['Generating: build.ninja'])
+test.must_exist(test.workpath('build.ninja'))
+test.must_not_exist(test.workpath('test2' + _exe))
+
+test.pass_test()