Do not analyse stub files with errors when the result cache is restored

The errors of the stub validation are kept in the result cache under the
stub file. When a new file appeared, every file with errors was re-analysed,
the stub file too, so the rules for analysed files reported errors in it,
such as a missing return statement in each method without a body.

Amp-Thread-ID: https://ampcode.com/threads/T-01a18c38-cedb-76c4-8a09-c5e85fea5b60

Author: ondrejmirtes

.github/workflows/e2e-tests.yml

@@ -186,6 +186,21 @@ jobs:
               OUTPUT=$(../../bin/phpstan -vvv 2>&1)
               echo "$OUTPUT"
               ../bashunit assert contains 'Result cache restored.' "$OUTPUT"
+          - script: |
+              cd e2e/result-cache-stub-files-errors
+              # The stub file is validated on the full analysis, and its error is kept in the result cache.
+              OUTPUT=$(../bashunit assert exit_code "1" "../../bin/phpstan analyse --error-format raw")
+              echo "$OUTPUT"
+              ../bashunit assert contains 'test.stub:8:Method StubFilesResultCache\Foo::doFoo() has parameter $a with no type specified.' "$OUTPUT"
+              ../bashunit assert not_contains 'return statement is missing' "$OUTPUT"
+              # A new file makes the files with errors re-analysed. The stub file is not one of them,
+              # otherwise the rules for analysed files would report that doFoo() does not return.
+              echo '<?php function doBaz(): void {}' > src/Baz.php
+              OUTPUT=$(../bashunit assert exit_code "1" "../../bin/phpstan analyse -vv --error-format raw")
+              echo "$OUTPUT"
+              ../bashunit assert contains 'Result cache restored.' "$OUTPUT"
+              ../bashunit assert contains 'test.stub:8:Method StubFilesResultCache\Foo::doFoo() has parameter $a with no type specified.' "$OUTPUT"
+              ../bashunit assert not_contains 'return statement is missing' "$OUTPUT"
           - script: |
               cd e2e/result-cache-worker-count
               OUTPUT=$(../../bin/phpstan -vvv 2>&1)

.gitignore

@@ -25,6 +25,7 @@ e2e/bashunit
 /e2e/result-cache-collected-data-rules/tmp
 /e2e/result-cache-collected-data-rules-tracking/tmp
 /e2e/result-cache-truncated/tmp
+/e2e/result-cache-stub-files-errors/tmp
 /e2e/result-cache-worker-count/tmp
 e2e/restart-manager/probe.log
 e2e/restart-manager/starts.log

e2e/result-cache-stub-files-errors/phpstan.neon

@@ -0,0 +1,7 @@
+parameters:
+	level: 8
+	tmpDir: tmp
+	stubFiles:
+		- stubs/test.stub
+	paths:
+		- src

e2e/result-cache-stub-files-errors/src/Bar.php

@@ -0,0 +1,8 @@
+<?php
+
+namespace StubFilesResultCache;
+
+function doBar(): string
+{
+	return '';
+}

e2e/result-cache-stub-files-errors/stubs/test.stub

@@ -0,0 +1,13 @@
+<?php
+
+namespace StubFilesResultCache;
+
+class Foo
+{
+
+	public function doFoo($a): string
+	{
+
+	}
+
+}

src/Analyser/ResultCache/ResultCacheManager.php

@@ -1028,6 +1028,12 @@ public function restore(array $allAnalysedFiles, bool $debug, bool $onlyFiles, ?
 
 		if ($newFileAppeared || $notAnalysedFileSymbolsChanged) {
 			foreach (array_keys($filteredErrors) as $fileWithError) {
+				// A stub file has errors from the stub validation, which runs on the full analysis only.
+				// It is not an analysed file, so analysing it would report the errors of all rules in it.
+				if (array_key_exists($fileWithError, $cachedStubFiles)) {
+					continue;
+				}
+
 				$filesToAnalyse[] = $fileWithError;
 			}
 		}