1 files changed, 46 insertions, 0 deletions
diff --git a/test/fixedbugs/issue21979.go b/test/fixedbugs/issue21979.go
new file mode 100644
index 00000000..1c02f574
--- /dev/null
+++ b/test/fixedbugs/issue21979.go
@@ -0,0 +1,46 @@
+// errorcheck
+
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+func f() {
+	_ = bool("")      // ERROR "cannot convert .. \(type untyped string\) to type bool"
+	_ = bool(1)       // ERROR "cannot convert 1 \(type untyped int\) to type bool"
+	_ = bool(1.0)     // ERROR "cannot convert 1 \(type untyped float\) to type bool"
+	_ = bool(-4 + 2i) // ERROR "cannot convert -4 \+ 2i \(type untyped complex\) to type bool"
+
+	_ = string(true) // ERROR "cannot convert true \(type untyped bool\) to type string"
+	_ = string(-1)
+	_ = string(1.0)     // ERROR "cannot convert 1 \(type untyped float\) to type string"
+	_ = string(-4 + 2i) // ERROR "cannot convert -4 \+ 2i \(type untyped complex\) to type string"
+
+	_ = int("")   // ERROR "cannot convert .. \(type untyped string\) to type int"
+	_ = int(true) // ERROR "cannot convert true \(type untyped bool\) to type int"
+	_ = int(-1)
+	_ = int(1)
+	_ = int(1.0)
+	_ = int(-4 + 2i) // ERROR "truncated to integer"
+
+	_ = uint("")   // ERROR "cannot convert .. \(type untyped string\) to type uint"
+	_ = uint(true) // ERROR "cannot convert true \(type untyped bool\) to type uint"
+	_ = uint(-1)   // ERROR "constant -1 overflows uint"
+	_ = uint(1)
+	_ = uint(1.0)
+	_ = uint(-4 + 2i) // ERROR "constant -4 overflows uint" "truncated to integer"
+
+	_ = float64("")   // ERROR "cannot convert .. \(type untyped string\) to type float64"
+	_ = float64(true) // ERROR "cannot convert true \(type untyped bool\) to type float64"
+	_ = float64(-1)
+	_ = float64(1)
+	_ = float64(1.0)
+	_ = float64(-4 + 2i) // ERROR "truncated to real"
+
+	_ = complex128("")   // ERROR "cannot convert .. \(type untyped string\) to type complex128"
+	_ = complex128(true) // ERROR "cannot convert true \(type untyped bool\) to type complex128"
+	_ = complex128(-1)
+	_ = complex128(1)
+	_ = complex128(1.0)
+}