Merge pull request #1887 from tanadeau/sr-1052-add-attr

[WIP][Parser][SR-1052] Added @discardableResult attribute parsing.
apple · Apr 3, 2016 · 679853d · 679853d
2 parents c767b9f + 3b5a8cd
commit 679853d
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Showing 7 changed files with 41 additions and 2 deletions.
diff --git a/include/swift/AST/Attr.def b/include/swift/AST/Attr.def
@@ -259,6 +259,9 @@ SIMPLE_DECL_ATTR(_versioned, Versioned,
                  LongAttribute | UserInaccessible,
                  64)
 
+SIMPLE_DECL_ATTR(discardableResult, DiscardableResult,
+                 OnFunc | OnConstructor | LongAttribute, 65)
+
 #undef TYPE_ATTR
 #undef DECL_ATTR_ALIAS
 #undef SIMPLE_DECL_ATTR

diff --git a/include/swift/AST/PrintOptions.h b/include/swift/AST/PrintOptions.h
@@ -347,6 +347,7 @@ struct PrintOptions {
     result.SkipUnderscoredStdlibProtocols = true;
     result.SkipDeinit = true;
     result.ExcludeAttrList.push_back(DAK_WarnUnusedResult);
+    result.ExcludeAttrList.push_back(DAK_DiscardableResult);
     result.EmptyLineBetweenMembers = true;
     result.ElevateDocCommentFromConformance = true;
     return result;

diff --git a/lib/Sema/TypeCheckAttr.cpp b/lib/Sema/TypeCheckAttr.cpp
@@ -82,6 +82,7 @@ class AttributeEarlyChecker : public AttributeVisitor<AttributeEarlyChecker> {
   IGNORED_ATTR(Versioned)
   IGNORED_ATTR(WarnUnusedResult)
   IGNORED_ATTR(ShowInInterface)
+  IGNORED_ATTR(DiscardableResult)
 #undef IGNORED_ATTR
 
   void visitAlignmentAttr(AlignmentAttr *attr) {
@@ -653,6 +654,7 @@ class AttributeChecker : public AttributeVisitor<AttributeChecker> {
     IGNORED_ATTR(Testable)
     IGNORED_ATTR(WarnUnqualifiedAccess)
     IGNORED_ATTR(ShowInInterface)
+    IGNORED_ATTR(DiscardableResult)
 
     // FIXME: We actually do have things to enforce for versioned API.
     IGNORED_ATTR(Versioned)

diff --git a/lib/Sema/TypeCheckDecl.cpp b/lib/Sema/TypeCheckDecl.cpp
@@ -5123,6 +5123,7 @@ class DeclChecker : public DeclVisitor<DeclChecker> {
 
     UNINTERESTING_ATTR(WarnUnusedResult)
     UNINTERESTING_ATTR(WarnUnqualifiedAccess)
+    UNINTERESTING_ATTR(DiscardableResult)
 
 #undef UNINTERESTING_ATTR
 

diff --git a/test/IDE/complete_decl_attribute.swift b/test/IDE/complete_decl_attribute.swift
@@ -43,7 +43,7 @@ func method(@#^KEYWORD1^#) {}
 @#^KEYWORD2^#
 func method(){}
 
-// KEYWORD2:                  Begin completions, 10 items
+// KEYWORD2:                  Begin completions, 11 items
 // KEYWORD2-NEXT:             Keyword/None:                       available[#Func Attribute#]; name=available{{$}}
 // KEYWORD2-NEXT:             Keyword/None:                       objc[#Func Attribute#]; name=objc{{$}}
 // KEYWORD2-NEXT:             Keyword/None:                       swift3_migration[#Func Attribute#]; name=swift3_migration{{$}}
@@ -54,6 +54,7 @@ func method(){}
 // KEYWORD2-NEXT:             Keyword/None:                       nonobjc[#Func Attribute#]; name=nonobjc{{$}}
 // KEYWORD2-NEXT:             Keyword/None:                       warn_unused_result[#Func Attribute#]; name=warn_unused_result{{$}}
 // KEYWORD2-NEXT:             Keyword/None:                       warn_unqualified_access[#Func Attribute#]; name=warn_unqualified_access{{$}}
+// KEYWORD2-NEXT:             Keyword/None:                       discardableResult[#Func Attribute#]; name=discardableResult
 // KEYWORD2-NEXT:             End completions
 
 @#^KEYWORD3^#
@@ -89,7 +90,7 @@ struct S{}
 
 @#^KEYWORD_LAST^#
 
-// KEYWORD_LAST:                  Begin completions, 20 items
+// KEYWORD_LAST:                  Begin completions, 21 items
 // KEYWORD_LAST-NEXT:             Keyword/None:                       available[#Declaration Attribute#]; name=available{{$}}
 // KEYWORD_LAST-NEXT:             Keyword/None:                       objc[#Declaration Attribute#]; name=objc{{$}}
 // KEYWORD_LAST-NEXT:             Keyword/None:                       swift3_migration[#Declaration Attribute#]; name=swift3_migration{{$}}
@@ -110,4 +111,5 @@ struct S{}
 // KEYWORD_LAST-NEXT:             Keyword/None:                       objc_non_lazy_realization[#Declaration Attribute#]; name=objc_non_lazy_realization{{$}}
 // KEYWORD_LAST-NEXT:             Keyword/None:                       warn_unused_result[#Declaration Attribute#]; name=warn_unused_result
 // KEYWORD_LAST-NEXT:             Keyword/None:                       warn_unqualified_access[#Declaration Attribute#]; name=warn_unqualified_access
+// KEYWORD_LAST-NEXT:             Keyword/None:                       discardableResult[#Declaration Attribute#]; name=discardableResult
 // KEYWORD_LAST-NEXT:             End completions
diff --git a/test/IDE/print_ast_tc_decls.swift b/test/IDE/print_ast_tc_decls.swift
@@ -1311,6 +1311,19 @@ public struct ArrayThingy {
     public func mineCopper() -> Int { return 0 }
 }
 
+// @discardableResult attribute
+public struct DiscardableThingy {
+    // PASS_PRINT_AST: @discardableResult
+    // PASS_PRINT_AST-NEXT: public init()
+    @discardableResult
+    public init() {}
+
+    // PASS_PRINT_AST: @discardableResult
+    // PASS_PRINT_AST-NEXT: public func useless() -> Int
+    @discardableResult
+    public func useless() -> Int { return 0 }
+}
+
 
 // Parameter Attributes.
 

diff --git a/test/attr/attr_discardableResult.swift b/test/attr/attr_discardableResult.swift
@@ -0,0 +1,17 @@
+// RUN: %target-parse-verify-swift
+
+// ---------------------------------------------------------------------------
+// Mark function's return value as discardable and silence warning
+// ---------------------------------------------------------------------------
+@discardableResult func f1() -> [Int] { }
+
+class C1 {
+  @discardableResult init() { }
+
+  @discardableResult
+  func f1() -> Int { }
+}
+
+struct Inits1 {
+  @discardableResult init() { }
+}