Add Regression Test for rdar://74583179

Author: CodaFi

test/Incremental/Fingerprints/Inputs/extension-changes-member/definesS-after.swift

@@ -0,0 +1,8 @@
+public struct S {
+  private // commenting out this line works
+  static func foo(_ i: Int) {print("1: other:2 commented out")}
+}
+extension S {
+  // private // commenting out this line fails
+  static func foo2(_ i: Int) {print("2: other:6 commented out")}
+}

test/Incremental/Fingerprints/Inputs/extension-changes-member/definesS-before.swift

@@ -0,0 +1,8 @@
+public struct S {
+  private // commenting out this line works
+  static func foo(_ i: Int) {print("1: other:2 commented out")}
+}
+extension S {
+  private // commenting out this line fails
+  static func foo2(_ i: Int) {print("2: other:6 commented out")}
+}

test/Incremental/Fingerprints/Inputs/extension-changes-member/main.swift

@@ -0,0 +1,11 @@
+extension S {
+  static func foo<I: SignedInteger>(_ si: I) {
+    print("1: other:2 not commented out")
+  }
+  static func foo2<I: SignedInteger>(_ si: I) {
+    print("2: other:6 not commented out")
+  }
+}
+
+S.foo(3)
+S.foo2(3)

test/Incremental/Fingerprints/Inputs/extension-changes-member/ofm.json

@@ -0,0 +1,14 @@
+{
+  "main.swift": {
+    "object": "./main.o",
+    "swift-dependencies": "./main.swiftdeps"
+  },
+  "definesS.swift": {
+    "object": "./definesS.o",
+    "swift-dependencies": "./definesS.swiftdeps"
+  },
+  "": {
+    "swift-dependencies": "./main~buildrecord.swiftdeps"
+  }
+}
+

test/Incremental/Fingerprints/extension-changes-member.swift

@@ -0,0 +1,32 @@
+// Test per-type-body fingerprints using simple extensions
+//
+// If the parser is allowed to use a body fingerprint for an extension
+// this test will fail because usesA.swift won't be recompiled for the
+// last step.
+
+// Establish status quo
+
+// RUN: %empty-directory(%t)
+// RUN: cp %S/Inputs/extension-changes-member/* %t
+// RUN: cp %t/definesS{-before,}.swift
+
+// Seeing weird failure on CI, so set the mod times
+// RUN: touch -t 200101010101 %t/*.swift
+
+// RUN: cd %t && %target-swiftc_driver  -enable-batch-mode -j2 -incremental -driver-show-incremental main.swift definesS.swift -module-name main -output-file-map ofm.json  >& %t/output3
+
+// Change one type, only uses of that type get recompiled
+
+// RUN: cp %t/definesS{-after,}.swift
+
+// Seeing weird failure on CI, so ensure that definesS.swift is newer
+// RUN: touch -t 200201010101 %t/*
+// RUN: touch -t 200101010101 %t/*.swift
+// RUN: touch -t 200301010101 %t/definesS.swift
+
+// RUN: cd %t && %target-swiftc_driver  -enable-batch-mode -j2 -incremental -driver-show-incremental main.swift definesS.swift -module-name main -output-file-map ofm.json  >& %t/output4
+
+// RUN: %FileCheck -check-prefix=CHECK-RECOMPILED-W %s < %t/output4
+
+// CHECK-RECOMPILED-W: {compile: definesS.o <= definesS.swift}
+// CHECK-RECOMPILED-W: {compile: main.o <= main.swift}