[CodeComplete] Complete a lambda when preferred type is a function

Summary: Uses a heuristic to detect std::function and friends.

Reviewers: kadircet

Reviewed By: kadircet

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D62238

llvm-svn: 361461

1 files changed, 53 insertions, 0 deletions

diff --git a/clang/test/CodeCompletion/lambdas.cpp b/clang/test/CodeCompletion/lambdas.cpp
new file mode 100644
index 00000000000..3467cec0e3b
--- /dev/null
+++ b/clang/test/CodeCompletion/lambdas.cpp
@@ -0,0 +1,53 @@
+template <class T>
+struct function {
+};
+
+
+void test() {
+  void (*x)(int, double) = nullptr;
+
+  function<void(int, double)> y = {};
+  // RUN: %clang_cc1 -fsyntax-only -code-completion-patterns -code-completion-at=%s:7:28 %s -o - | FileCheck -check-prefix=CHECK-1 %s
+  // RUN: %clang_cc1 -fsyntax-only -code-completion-patterns -code-completion-at=%s:9:35 %s -o - | FileCheck -check-prefix=CHECK-1 %s
+  // CHECK-1: COMPLETION: Pattern : [<#=#>](int <#parameter#>, double <#parameter#>){<#body#>}
+
+  // == Placeholders for suffix types must be placed properly.
+  function<void(void(*)(int))> z = {};
+  // RUN: %clang_cc1 -fsyntax-only -code-completion-patterns -code-completion-at=%s:15:36 %s -o - | FileCheck -check-prefix=CHECK-2 %s
+  // CHECK-2: COMPLETION: Pattern : [<#=#>](void (* <#parameter#>)(int)){<#body#>}
+
+  // == No need for a parameter list if function has no parameters.
+  function<void()> a = {};
+  // RUN: %clang_cc1 -fsyntax-only -code-completion-patterns -code-completion-at=%s:20:24 %s -o - | FileCheck -check-prefix=CHECK-3 %s
+  // CHECK-3: COMPLETION: Pattern : [<#=#>]{<#body#>}
+}
+
+template <class T, class Allocator = int>
+struct vector {};
+
+void test2() {
+  // == Try to preserve types as written.
+  function<void(vector<int>)> a = {};
+
+  using function_typedef = function<void(vector<int>)>;
+  function_typedef b = {};
+  // RUN: %clang_cc1 -fsyntax-only -code-completion-patterns -code-completion-at=%s:30:35 %s -o - | FileCheck -check-prefix=CHECK-4 %s
+  // RUN: %clang_cc1 -fsyntax-only -code-completion-patterns -code-completion-at=%s:33:24 %s -o - | FileCheck -check-prefix=CHECK-4 %s
+  // CHECK-4: COMPLETION: Pattern : [<#=#>](vector<int> <#parameter#>){<#body#>}
+}
+
+// Check another common function wrapper name.
+template <class T> struct unique_function {};
+
+void test3() {
+  unique_function<void()> a = {};
+  // RUN: %clang_cc1 -fsyntax-only -code-completion-patterns -code-completion-at=%s:43:31 %s -o - | FileCheck -check-prefix=CHECK-5 %s
+  // CHECK-5: COMPLETION: Pattern : [<#=#>]{<#body#>}
+}
+
+template <class T, class U> struct weird_function {};
+void test4() {
+  weird_function<void(), int> b = {};
+  // RUN: %clang_cc1 -fsyntax-only -code-completion-patterns -code-completion-at=%s:50:35 %s -o - | FileCheck -check-prefix=CHECK-6 %s
+  // CHECK-6-NOT: COMPLETION: Pattern : [<#=
+}