Make Test spec JSON generator hashless.

Removes scripts/code_generation_hashes/Test_spec_JSON.json

Instead, run codegen in --verify-only mode and compare content.
This run during presubmits and is fast (~0.2s in my tests)

Similar to https://crrev.com/c/4604579

With this, should be able to auto-resolve conflicts in
infra/specs/angle.json

Also testing/buildbot/mixins.pyl
seems to have had hashes routinely updated by autorolls.

Bug: angleproject:8193
Change-Id: Ic1a657dbf464e6f4a8066ea8c5e18297e27a3b4c
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/4605467
Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Auto-Submit: Roman Lavrov <romanl@google.com>
Commit-Queue: Roman Lavrov <romanl@google.com>
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>

infra/specs/generate_test_spec_json.py

@@ -13,6 +13,7 @@ import os
 import pprint
 import sys
 import subprocess
+import tempfile
 
 d = os.path.dirname
 THIS_DIR = d(os.path.abspath(__file__))
@@ -84,18 +85,44 @@ def main():
         outputs = ['angle.json', 'mixins.pyl']
         if sys.argv[1] == 'inputs':
             print(','.join(inputs))
-        elif sys.argv[1] == 'outputs':
+            return 0
+        if sys.argv[1] == 'outputs':
             print(','.join(outputs))
-        else:
-            print('Invalid script parameters')
-            return 1
-        return 0
+            return 0
 
-    chromium_args = generate_buildbot_json.BBJSONGenerator.parse_args(sys.argv[1:])
+    # --verify-only enables dirty checks without relying on checked in hashes.
+    # Compares the content of the existing file with the generated content.
+    verify_only = '--verify-only' in sys.argv
+
+    if verify_only:
+        with tempfile.TemporaryDirectory() as temp_dir:
+            return run_generator(verify_only, temp_dir)
+    else:
+        return run_generator(verify_only, None)
+
+
+def write_or_verify_file(filename, content, verify_only):
+    if verify_only:
+        try:
+            with open(filename) as f:
+                # Note: .gitattributes "* text=auto" handles LF <-> CRLF on Windows
+                return f.read() == content
+        except FileNotFoundError:
+            return False
+    else:
+        with open(filename, 'w') as fout:
+            fout.write(content)
+            return True
+
+
+def run_generator(verify_only, temp_dir):
+    chromium_args = generate_buildbot_json.BBJSONGenerator.parse_args([])
     chromium_generator = generate_buildbot_json.BBJSONGenerator(chromium_args)
     chromium_generator.load_configuration_files()
 
-    override_args = sys.argv[1:] + ['--pyl-files-dir', THIS_DIR]
+    override_args = ['--pyl-files-dir', THIS_DIR]
+    if verify_only:
+        override_args += ['--output-dir', temp_dir]
     angle_args = generate_buildbot_json.BBJSONGenerator.parse_args(override_args)
     angle_generator = generate_buildbot_json.BBJSONGenerator(angle_args)
     angle_generator.load_configuration_files()
@@ -131,11 +158,25 @@ def main():
     }
     generated_mixin_pyl = MIXINS_PYL_TEMPLATE.format(**format_data)
 
-    with open(MIXIN_FILE_NAME, 'w') as f:
-        f.write(generated_mixin_pyl)
-        f.close()
+    if not write_or_verify_file(MIXIN_FILE_NAME, generated_mixin_pyl, verify_only):
+        print('infra/specs/mixins.pyl dirty')
+        return 1
 
-    return angle_generator.main()
+    if angle_generator.main() != 0:
+        print('buildbot (pyl to json) generation failed')
+        return 1
+
+    if verify_only:
+        for waterfall in angle_generator.waterfalls:
+            filename = waterfall['name'] + '.json'  # angle.json, might have more in future
+            with open(os.path.join(temp_dir, filename)) as f:
+                content = f.read()
+            angle_filename = os.path.join(THIS_DIR, filename)
+            if not write_or_verify_file(angle_filename, content, True):
+                print('infra/specs/%s dirty' % filename)
+                return 1
+
+    return 0
 
 
 if __name__ == '__main__':  # pragma: no cover

scripts/code_generation_hashes/Test_spec_JSON.json

@@ -1,20 +0,0 @@
-{
-  "infra/specs/angle.json":
-    "767f56197f6f853c88c9bd6221a71983",
-  "infra/specs/generate_test_spec_json.py":
-    "b8dbb50c814b7fe05eb77cf6e376cee4",
-  "infra/specs/mixins.pyl":
-    "54a3f8bd82fa04025538a2d96f163066",
-  "infra/specs/test_suite_exceptions.pyl":
-    "55886f8b6ae4122306ce42083c5126c7",
-  "infra/specs/test_suites.pyl":
-    "64dbc702fcf98524edd79a154e97efb9",
-  "infra/specs/variants.pyl":
-    "8cfcaa99fa07ad2a2d5d14f220fd5037",
-  "infra/specs/waterfalls.pyl":
-    "dc0b858cd95192e7b5695b80c57a5614",
-  "testing/buildbot/generate_buildbot_json.py":
-    "981e4588c647f09b090f028bd9816d51",
-  "testing/buildbot/mixins.pyl":
-    "73791de121604a26f47488ce160593aa"
-}

scripts/run_code_generation.py

@@ -120,8 +120,6 @@ generators = {
         'src/common/spirv/gen_spirv_builder_and_parser.py',
     'Static builtins':
         'src/compiler/translator/gen_builtin_symbols.py',
-    'Test spec JSON':
-        'infra/specs/generate_test_spec_json.py',
     'uniform type':
         'src/common/gen_uniform_type_table.py',
     'Vulkan format':
@@ -136,6 +134,7 @@ generators = {
 # Fast and supports --verify-only without hashes.
 hashless_generators = {
     'ANGLE features': 'include/platform/gen_features.py',
+    'Test spec JSON': 'infra/specs/generate_test_spec_json.py',
 }