api-digester: teach the tool to detect new mutating/throwing functions (#5284)

Author: nkcsgexi

test/api-digester/Inputs/cake1.swift

@@ -0,0 +1,4 @@
+public struct S1 {
+  mutating public func foo1() {}
+  mutating public func foo2() {}
+}

test/api-digester/Outputs/Cake.txt

@@ -0,0 +1,11 @@
+
+==================================================== Removed Decls ====================================================
+
+==================================================== Moved Decls ====================================================
+
+==================================================== Renamed Decls ====================================================
+
+==================================================== Type Changes ====================================================
+
+==================================================== Decl Attribute changes ====================================================
+FuncS1.foo1() is now mutating

test/api-digester/compare-dump.swift

@@ -0,0 +1,9 @@
+// RUN: rm -rf %t.mod && mkdir -p %t.mod
+// RUN: rm -rf %t.sdk && mkdir -p %t.sdk
+// RUN: rm -rf %t.module-cache && mkdir -p %t.module-cache
+// RUN: %swift -emit-module -o %t.mod/cake.swiftmodule %S/Inputs/cake.swift -parse-as-library
+// RUN: %swift -emit-module -o %t.mod/cake1.swiftmodule %S/Inputs/cake1.swift -parse-as-library
+// RUN: %api-digester -dump-sdk -module cake -o %t.dump.json -module-cache-path %t.module-cache -sdk %t.sdk -swift-version 3.0 -I %t.mod
+// RUN: %api-digester -dump-sdk -module cake1 -o %t.dump1.json -module-cache-path %t.module-cache -sdk %t.sdk -swift-version 3.0 -I %t.mod
+// RUN: %api-digester -diagnose-sdk --input-paths %t.dump.json -input-paths %t.dump1.json > %t.result
+// RUN: diff -u %S/Outputs/Cake.txt %t.result

test/api-digester/source-stability.swift.expected

@@ -17,4 +17,6 @@ Func Float80.abs(_:) has been moved to Func abs(_:)
 ==================================================== Renamed Decls ====================================================
 
 ==================================================== Type Changes ====================================================
-Func UnsafePointer.withMemoryRebound(to:capacity:_:) has 3rd parameter type change from (UnsafeMutablePointer<T>) throws -> Result to (UnsafePointer<T>) throws -> Result
+Func UnsafePointer.withMemoryRebound(to:capacity:_:) has 3rd parameter type change from (UnsafeMutablePointer<T>) throws -> Result to (UnsafePointer<T>) throws -> Result
+
+==================================================== Decl Attribute changes ====================================================