fix: Add stubs for more missing reflect methods

With these methods stubbed out, the text/template package can be
imported. These changes also allow code generated by protoc to compile.

src/reflect/value.go

@@ -128,7 +128,7 @@ func (v Value) IsNil() bool {
 		_, val := decomposeInterface(*(*interface{})(v.value))
 		return val == nil
 	default:
-		panic(&ValueError{"IsNil"})
+		panic(&ValueError{Method: "IsNil"})
 	}
 }
 
@@ -144,7 +144,7 @@ func (v Value) Pointer() uintptr {
 	case Func:
 		panic("unimplemented: (reflect.Value).Pointer()")
 	default: // not implemented: Func
-		panic(&ValueError{"Pointer"})
+		panic(&ValueError{Method: "Pointer"})
 	}
 }
 
@@ -187,7 +187,7 @@ func (v Value) Bool() bool {
 			return uintptr(v.value) != 0
 		}
 	default:
-		panic(&ValueError{"Bool"})
+		panic(&ValueError{Method: "Bool"})
 	}
 }
 
@@ -224,7 +224,7 @@ func (v Value) Int() int64 {
 			return int64(int64(uintptr(v.value)))
 		}
 	default:
-		panic(&ValueError{"Int"})
+		panic(&ValueError{Method: "Int"})
 	}
 }
 
@@ -267,7 +267,7 @@ func (v Value) Uint() uint64 {
 			return uint64(uintptr(v.value))
 		}
 	default:
-		panic(&ValueError{"Uint"})
+		panic(&ValueError{Method: "Uint"})
 	}
 }
 
@@ -293,7 +293,7 @@ func (v Value) Float() float64 {
 			return *(*float64)(unsafe.Pointer(&v.value))
 		}
 	default:
-		panic(&ValueError{"Float"})
+		panic(&ValueError{Method: "Float"})
 	}
 }
 
@@ -315,7 +315,7 @@ func (v Value) Complex() complex128 {
 		// architectures with 128-bit pointers, however.
 		return *(*complex128)(v.value)
 	default:
-		panic(&ValueError{"Complex"})
+		panic(&ValueError{Method: "Complex"})
 	}
 }
 
@@ -339,6 +339,10 @@ func (v Value) Slice(i, j int) Value {
 	panic("unimplemented: (reflect.Value).Slice()")
 }
 
+func (v Value) Slice3(i, j, k int) Value {
+	panic("unimplemented: (reflect.Value).Slice3()")
+}
+
 //go:linkname maplen runtime.hashmapLenUnsafePointer
 func maplen(p unsafe.Pointer) int
 
@@ -360,7 +364,7 @@ func (v Value) Len() int {
 	case String:
 		return int((*stringHeader)(v.value).len)
 	default:
-		panic(&ValueError{"Len"})
+		panic(&ValueError{Method: "Len"})
 	}
 }
 
@@ -378,7 +382,7 @@ func (v Value) Cap() int {
 	case Slice:
 		return int((*sliceHeader)(v.value).cap)
 	default:
-		panic(&ValueError{"Cap"})
+		panic(&ValueError{Method: "Cap"})
 	}
 }
 
@@ -408,7 +412,7 @@ func (v Value) Elem() Value {
 			flags:    v.flags &^ valueFlagIndirect,
 		}
 	default:
-		panic(&ValueError{"Elem"})
+		panic(&ValueError{Method: "Elem"})
 	}
 }
 
@@ -552,7 +556,7 @@ func (v Value) Index(i int) Value {
 			value:    unsafe.Pointer(value),
 		}
 	default:
-		panic(&ValueError{"Index"})
+		panic(&ValueError{Method: "Index"})
 	}
 }
 
@@ -631,7 +635,7 @@ func (v Value) SetBool(x bool) {
 	case Bool:
 		*(*bool)(v.value) = x
 	default:
-		panic(&ValueError{"SetBool"})
+		panic(&ValueError{Method: "SetBool"})
 	}
 }
 
@@ -649,7 +653,7 @@ func (v Value) SetInt(x int64) {
 	case Int64:
 		*(*int64)(v.value) = x
 	default:
-		panic(&ValueError{"SetInt"})
+		panic(&ValueError{Method: "SetInt"})
 	}
 }
 
@@ -669,7 +673,7 @@ func (v Value) SetUint(x uint64) {
 	case Uintptr:
 		*(*uintptr)(v.value) = uintptr(x)
 	default:
-		panic(&ValueError{"SetUint"})
+		panic(&ValueError{Method: "SetUint"})
 	}
 }
 
@@ -681,7 +685,7 @@ func (v Value) SetFloat(x float64) {
 	case Float64:
 		*(*float64)(v.value) = x
 	default:
-		panic(&ValueError{"SetFloat"})
+		panic(&ValueError{Method: "SetFloat"})
 	}
 }
 
@@ -693,7 +697,7 @@ func (v Value) SetComplex(x complex128) {
 	case Complex128:
 		*(*complex128)(v.value) = x
 	default:
-		panic(&ValueError{"SetComplex"})
+		panic(&ValueError{Method: "SetComplex"})
 	}
 }
 
@@ -703,7 +707,7 @@ func (v Value) SetString(x string) {
 	case String:
 		*(*string)(v.value) = x
 	default:
-		panic(&ValueError{"SetString"})
+		panic(&ValueError{Method: "SetString"})
 	}
 }
 
@@ -788,10 +792,14 @@ type stringHeader struct {
 
 type ValueError struct {
 	Method string
+	Kind   Kind
 }
 
 func (e *ValueError) Error() string {
-	return "reflect: call of reflect.Value." + e.Method + " on invalid type"
+	if e.Kind == 0 {
+		return "reflect: call of " + e.Method + " on zero Value"
+	}
+	return "reflect: call of " + e.Method + " on " + e.Kind.String() + " Value"
 }
 
 // Calls to this function are converted to LLVM intrinsic calls such as
@@ -865,3 +873,15 @@ func MakeMap(typ Type) Value {
 func (v Value) Call(in []Value) []Value {
 	panic("unimplemented: (reflect.Value).Call()")
 }
+
+func (v Value) MethodByName(name string) Value {
+	panic("unimplemented: (reflect.Value).MethodByName()")
+}
+
+func (v Value) Recv() (x Value, ok bool) {
+	panic("unimplemented: (reflect.Value).Recv()")
+}
+
+func NewAt(typ Type, p unsafe.Pointer) Value {
+	panic("unimplemented: reflect.New()")
+}