cmd/compile: use "missing method m" instead of "missing m method"

For #55326

Change-Id: I3d0ff7f820f7b2009d1b226abf701b2337fe8cbc
Reviewed-on: https://go-review.googlesource.com/c/go/+/432635
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Robert Griesemer <gri@google.com>
Run-TryBot: Robert Griesemer <gri@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>
Run-TryBot: xie cui <523516579@qq.com>
Reviewed-by: Robert Griesemer <gri@google.com>
diff --git a/src/cmd/compile/internal/types2/lookup.go b/src/cmd/compile/internal/types2/lookup.go
index 1deea0b..3a158f7 100644
--- a/src/cmd/compile/internal/types2/lookup.go
+++ b/src/cmd/compile/internal/types2/lookup.go
@@ -371,12 +371,7 @@
 // it may have a pointer receiver, or it may have the correct name except wrong case.
 // check may be nil.
 func (check *Checker) missingMethodReason(V, T Type, m, alt *Func) string {
-	var mname string
-	if check != nil && check.conf.CompilerErrorMessages {
-		mname = m.Name() + " method"
-	} else {
-		mname = "method " + m.Name()
-	}
+	mname := "method " + m.Name()
 
 	if alt != nil {
 		if m.Name() != alt.Name() {
diff --git a/src/go/types/lookup.go b/src/go/types/lookup.go
index 9356558..cb75c87 100644
--- a/src/go/types/lookup.go
+++ b/src/go/types/lookup.go
@@ -371,12 +371,7 @@
 // it may have a pointer receiver, or it may have the correct name except wrong case.
 // check may be nil.
 func (check *Checker) missingMethodReason(V, T Type, m, alt *Func) string {
-	var mname string
-	if check != nil && compilerErrorMessages {
-		mname = m.Name() + " method"
-	} else {
-		mname = "method " + m.Name()
-	}
+	mname := "method " + m.Name()
 
 	if alt != nil {
 		if m.Name() != alt.Name() {
diff --git a/test/fixedbugs/issue48471.go b/test/fixedbugs/issue48471.go
index 1b843c8..8b8d643 100644
--- a/test/fixedbugs/issue48471.go
+++ b/test/fixedbugs/issue48471.go
@@ -33,22 +33,22 @@
 func f(I)
 
 func g() {
-	f(new(T)) // ERROR "cannot use new\(T\) \(.*type \*T\) as type I in argument to f:\n\t\*T does not implement I \(missing M method\)"
+	f(new(T)) // ERROR "cannot use new\(T\) \(.*type \*T\) as type I in argument to f:\n\t\*T does not implement I \(missing method M\)"
 
 	var i I
-	i = new(T)    // ERROR "cannot use new\(T\) \(.*type \*T\) as type I in assignment:\n\t\*T does not implement I \(missing M method\)"
-	i = I(new(T)) // ERROR "cannot convert new\(T\) \(.*type \*T\) to type I:\n\t\*T does not implement I \(missing M method\)"
-	i = new(T2)   // ERROR "cannot use new\(T2\) \(.*type \*T2\) as type I in assignment:\n\t\*T2 does not implement I \(missing M method\)\n\t\thave m\(int\)\n\t\twant M\(int\)"
+	i = new(T)    // ERROR "cannot use new\(T\) \(.*type \*T\) as type I in assignment:\n\t\*T does not implement I \(missing method M\)"
+	i = I(new(T)) // ERROR "cannot convert new\(T\) \(.*type \*T\) to type I:\n\t\*T does not implement I \(missing method M\)"
+	i = new(T2)   // ERROR "cannot use new\(T2\) \(.*type \*T2\) as type I in assignment:\n\t\*T2 does not implement I \(missing method M\)\n\t\thave m\(int\)\n\t\twant M\(int\)"
 
-	i = new(T3) // ERROR "cannot use new\(T3\) \(.*type \*T3\) as type I in assignment:\n\t\*T3 does not implement I \(wrong type for M method\)\n\t\thave M\(string\)\n\t\twant M\(int\)"
+	i = new(T3) // ERROR "cannot use new\(T3\) \(.*type \*T3\) as type I in assignment:\n\t\*T3 does not implement I \(wrong type for method M\)\n\t\thave M\(string\)\n\t\twant M\(int\)"
 
-	i = T4{}   // ERROR "cannot use T4\{\} \(.*type T4\) as type I in assignment:\n\tT4 does not implement I \(M method has pointer receiver\)"
+	i = T4{}   // ERROR "cannot use T4\{\} \(.*type T4\) as type I in assignment:\n\tT4 does not implement I \(method M has pointer receiver\)"
 	i = new(I) // ERROR "cannot use new\(I\) \(.*type \*I\) as type I in assignment:\n\t\*I does not implement I \(type \*I is pointer to interface, not interface\)"
 
-	_ = i.(*T2) // ERROR "impossible type assertion: i.\(\*T2\)\n\t\*T2 does not implement I \(missing M method\)\n\t\thave m\(int\)\n\t\twant M\(int\)"
-	_ = i.(*T3) // ERROR "impossible type assertion: i.\(\*T3\)\n\t\*T3 does not implement I \(wrong type for M method\)\n\t\thave M\(string\)\n\t\twant M\(int\)"
-	_ = i.(T5)  // ERROR ""impossible type assertion: i.\(T5\)\n\tT5 does not implement I \(missing M method\)\n\t\thave m\(int\)\n\t\twant M\(int\)"
-	_ = i.(T6)  // ERROR "impossible type assertion: i.\(T6\)\n\tT6 does not implement I \(missing M method\)\n\t\thave m\(int\) string\n\t\twant M\(int\)"
+	_ = i.(*T2) // ERROR "impossible type assertion: i.\(\*T2\)\n\t\*T2 does not implement I \(missing method M\)\n\t\thave m\(int\)\n\t\twant M\(int\)"
+	_ = i.(*T3) // ERROR "impossible type assertion: i.\(\*T3\)\n\t\*T3 does not implement I \(wrong type for method M\)\n\t\thave M\(string\)\n\t\twant M\(int\)"
+	_ = i.(T5)  // ERROR ""impossible type assertion: i.\(T5\)\n\tT5 does not implement I \(missing method M\)\n\t\thave m\(int\)\n\t\twant M\(int\)"
+	_ = i.(T6)  // ERROR "impossible type assertion: i.\(T6\)\n\tT6 does not implement I \(missing method M\)\n\t\thave m\(int\) string\n\t\twant M\(int\)"
 
 	var t *T4
 	t = i // ERROR "cannot use i \(variable of type I\) as type \*T4 in assignment:\n\tneed type assertion"
diff --git a/test/fixedbugs/issue49005b.go b/test/fixedbugs/issue49005b.go
index 9bff4e9..61710e0 100644
--- a/test/fixedbugs/issue49005b.go
+++ b/test/fixedbugs/issue49005b.go
@@ -10,6 +10,6 @@
 
 func F() T
 
-var _ = F().(*X) // ERROR "impossible type assertion:( F\(\).\(\*X\))?\n\t\*X does not implement T \(missing M method\)"
+var _ = F().(*X) // ERROR "impossible type assertion:( F\(\).\(\*X\))?\n\t\*X does not implement T \(missing method M\)"
 
 type X struct{}
diff --git a/test/interface/explicit.go b/test/interface/explicit.go
index e18d684..ccdae78 100644
--- a/test/interface/explicit.go
+++ b/test/interface/explicit.go
@@ -43,11 +43,11 @@
 	// neither of these can work,
 	// because i has an extra method
 	// that t does not, so i cannot contain a t.
-	i = t // ERROR "incompatible|missing M method"
+	i = t // ERROR "incompatible|missing method M"
 	t = i // ERROR "incompatible|assignment$"
 
 	i = i2 // ok
-	i2 = i // ERROR "incompatible|missing N method"
+	i2 = i // ERROR "incompatible|missing method N"
 
 	i = I(i2)  // ok
 	i2 = I2(i) // ERROR "invalid|missing N method|cannot convert"
@@ -81,7 +81,7 @@
 var jj Int
 
 var m1 M = ii // ERROR "incompatible|missing"
-var m2 M = jj // ERROR "incompatible|wrong type for M method"
+var m2 M = jj // ERROR "incompatible|wrong type for method M"
 
 var m3 = M(ii) // ERROR "invalid|missing|cannot convert"
 var m4 = M(jj) // ERROR "invalid|wrong type for M method|cannot convert"
diff --git a/test/switch6.go b/test/switch6.go
index b9d9800..fd66df5 100644
--- a/test/switch6.go
+++ b/test/switch6.go
@@ -15,7 +15,7 @@
 // Verify that type switch statements with impossible cases are detected by the compiler.
 func f0(e error) {
 	switch e.(type) {
-	case int: // ERROR "impossible type switch case: (int\n\t)?e \(.*type error\) cannot have dynamic type int \(missing Error method\)"
+	case int: // ERROR "impossible type switch case: (int\n\t)?e \(.*type error\) cannot have dynamic type int \(missing method Error\)"
 	}
 }
 
@@ -41,6 +41,6 @@
 func f2() {
 	var i I
 	switch i.(type) {
-	case X: // ERROR "impossible type switch case: (X\n\t)?i \(.*type I\) cannot have dynamic type X \(Foo method has pointer receiver\)"
+	case X: // ERROR "impossible type switch case: (X\n\t)?i \(.*type I\) cannot have dynamic type X \(method Foo has pointer receiver\)"
 	}
 }