Verify --version output matches CHANGELOG (#2580)

The new version string looks like this:

  wasm-opt version 90 (version_90-18-g77329439d)

The version reported here is the version from the CMakeLists.txt file
followed by the git version in brackets.  We verify that the main
version here matches the CHANGELOG to prevent people from changing
one without changeing the other.

This will help with emscripten that wants to be able to programaticaly
check the --version of binaryen tools.

See emscripten-core/emscripten#10175

CMakeLists.txt

@@ -15,17 +15,16 @@ option(BYN_ENABLE_ASSERTIONS "Enable assertions" ON)
 if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/.git)
   find_package(Git QUIET REQUIRED)
   execute_process(COMMAND
-               "${GIT_EXECUTABLE}" --git-dir=${CMAKE_CURRENT_SOURCE_DIR}/.git describe --tags
+               "${GIT_EXECUTABLE}" --git-dir=${CMAKE_CURRENT_SOURCE_DIR}/.git describe --tags --match version_*
            RESULT_VARIABLE
-               GIT_HASH_RESULT
+               GIT_VERSION_RESULT
            OUTPUT_VARIABLE
-               GIT_HASH
+               GIT_VERSION
            OUTPUT_STRIP_TRAILING_WHITESPACE)
-  if(${GIT_HASH_RESULT})
-    message(WARNING "Error running git describe to determine version")
-    set(CMAKE_PROJECT_VERSION "(unable to determine version)")
+  if(${GIT_VERSION_RESULT})
+    message(FATAL_ERROR "Error running git describe to determine version")
   else()
-    set(CMAKE_PROJECT_VERSION "${GIT_HASH}")
+    set(CMAKE_PROJECT_VERSION "${CMAKE_PROJECT_VERSION} (${GIT_VERSION})")
   endif()
 endif()
 

check.py

@@ -35,6 +35,16 @@
     assert os.path.exists(shared.options.interpreter), 'interpreter not found'
 
 
+def get_changelog_version():
+    with open(os.path.join(shared.options.binaryen_root, 'CHANGELOG.md')) as f:
+        lines = f.readlines()
+    lines = [l for l in lines if len(l.split()) == 1]
+    lines = [l for l in lines if l.startswith('v')]
+    version = lines[0][1:]
+    print("Parsed CHANGELOG.md version: %s" % version)
+    return int(version)
+
+
 def run_help_tests():
     print('[ checking --help is useful... ]\n')
 
@@ -56,6 +66,7 @@ def run_help_tests():
         assert len(out.split('\n')) > 8, 'Expected some help, got:\n%s' % out
 
     print('[ checking --version ... ]\n')
+    changelog_version = get_changelog_version()
     for e in executables:
         print('.. %s --version' % e)
         out, err = subprocess.Popen([e, '--version'],
@@ -66,6 +77,10 @@ def run_help_tests():
         assert len(err) == 0, 'Expected no stderr, got:\n%s' % err
         assert os.path.basename(e).replace('.exe', '') in out, 'Expected version to contain program name, got:\n%s' % out
         assert len(out.strip().splitlines()) == 1, 'Expected only version info, got:\n%s' % out
+        parts = out.split()
+        assert parts[1] == 'version'
+        version = int(parts[2])
+        assert version == changelog_version
 
 
 def run_wasm_opt_tests():

src/support/command-line.cpp

@@ -58,7 +58,7 @@ Options::Options(const std::string& command, const std::string& description)
       "Output version information and exit",
       Arguments::Zero,
       [command](Options*, const std::string&) {
-        std::cout << command << " " << CMAKE_PROJECT_VERSION << "\n";
+        std::cout << command << " version " << CMAKE_PROJECT_VERSION << "\n";
         exit(0);
       });
   add("--help",