Implement convert string <- []byte

compiler.go

@@ -2066,8 +2066,19 @@ func (c *Compiler) parseConvert(typeFrom, typeTo types.Type, value llvm.Value) (
 		sizeFrom := c.targetData.TypeAllocSize(llvmTypeFrom)
 
 		if typeTo.Kind() == types.String {
+			switch typeFrom := typeFrom.Underlying().(type) {
+			case *types.Slice:
+				switch typeFrom.Elem().(*types.Basic).Kind() {
+				case types.Byte:
+					fn := c.mod.NamedFunction("runtime.stringFromBytes")
+					return c.builder.CreateCall(fn, []llvm.Value{value}, ""), nil
+				default:
 					return llvm.Value{}, errors.New("todo: convert to string: " + typeFrom.String())
 				}
+			default:
+				return llvm.Value{}, errors.New("todo: convert to string: " + typeFrom.String())
+			}
+		}
 
 		typeFrom := typeFrom.Underlying().(*types.Basic)
 		sizeTo := c.targetData.TypeAllocSize(llvmTypeTo)

src/runtime/string.go

@@ -9,7 +9,7 @@ import (
 // The underlying struct for the Go string type.
 type _string struct {
 	length lenType
-	ptr    *uint8
+	ptr    *byte
 }
 
 // Return true iff the strings match.
@@ -36,6 +36,15 @@ func stringConcat(x, y _string) _string {
 		buf := alloc(length)
 		memcpy(buf, unsafe.Pointer(x.ptr), uintptr(x.length))
 		memcpy(unsafe.Pointer(uintptr(buf)+uintptr(x.length)), unsafe.Pointer(y.ptr), uintptr(y.length))
-		return _string{lenType(length), (*uint8)(buf)}
+		return _string{lenType(length), (*byte)(buf)}
 	}
 }
+
+// Create a string from a []byte slice.
+func stringFromBytes(x []byte) _string {
+	buf := alloc(uintptr(len(x)))
+	for i, c := range x {
+		*(*byte)(unsafe.Pointer(uintptr(buf) + uintptr(i))) = c
+	}
+	return _string{lenType(len(x)), (*byte)(buf)}
+}