finish implementation of json matches by with diff view and tests

assert/assertions.go

@@ -21,6 +21,7 @@ import (
 	"github.com/pmezard/go-difflib/difflib"
 
 	// Wrapper around gopkg.in/yaml.v3
+	"github.com/stretchr/testify/assert/internal/jsonmatch"
 	"github.com/stretchr/testify/assert/yaml"
 )
 
@@ -210,7 +211,6 @@ the problem actually occurred in calling code.*/
 // of each stack frame leading from the current test to the assert call that
 // failed.
 func CallerInfo() []string {
-
 	var pc uintptr
 	var ok bool
 	var file string
@@ -475,7 +475,6 @@ func Equal(t TestingT, expected, actual interface{}, msgAndArgs ...interface{})
 	}
 
 	return true
-
 }
 
 // validateEqualArgs checks whether provided arguments can be safely used in the
@@ -530,7 +529,7 @@ func NotSame(t TestingT, expected, actual interface{}, msgAndArgs ...interface{}
 
 	same, ok := samePointers(expected, actual)
 	if !ok {
-		//fails when the arguments are not pointers
+		// fails when the arguments are not pointers
 		return !(Fail(t, "Both arguments must be pointers", msgAndArgs...))
 	}
 
@@ -549,7 +548,7 @@ func NotSame(t TestingT, expected, actual interface{}, msgAndArgs ...interface{}
 func samePointers(first, second interface{}) (same bool, ok bool) {
 	firstPtr, secondPtr := reflect.ValueOf(first), reflect.ValueOf(second)
 	if firstPtr.Kind() != reflect.Ptr || secondPtr.Kind() != reflect.Ptr {
-		return false, false //not both are pointers
+		return false, false // not both are pointers
 	}
 
 	firstType, secondType := reflect.TypeOf(first), reflect.TypeOf(second)
@@ -610,7 +609,6 @@ func EqualValues(t TestingT, expected, actual interface{}, msgAndArgs ...interfa
 	}
 
 	return true
-
 }
 
 // EqualExportedValues asserts that the types of two objects are equal and their public
@@ -665,7 +663,6 @@ func Exactly(t TestingT, expected, actual interface{}, msgAndArgs ...interface{}
 	}
 
 	return Equal(t, expected, actual, msgAndArgs...)
-
 }
 
 // NotNil asserts that the specified object is not nil.
@@ -715,7 +712,6 @@ func Nil(t TestingT, object interface{}, msgAndArgs ...interface{}) bool {
 
 // isEmpty gets whether the specified object is considered empty or not.
 func isEmpty(object interface{}) bool {
-
 	// get nil case out of the way
 	if object == nil {
 		return true
@@ -756,7 +752,6 @@ func Empty(t TestingT, object interface{}, msgAndArgs ...interface{}) bool {
 	}
 
 	return pass
-
 }
 
 // NotEmpty asserts that the specified object is NOT empty.  I.e. not nil, "", false, 0 or either
@@ -775,7 +770,6 @@ func NotEmpty(t TestingT, object interface{}, msgAndArgs ...interface{}) bool {
 	}
 
 	return pass
-
 }
 
 // getLen tries to get the length of an object.
@@ -819,7 +813,6 @@ func True(t TestingT, value bool, msgAndArgs ...interface{}) bool {
 	}
 
 	return true
-
 }
 
 // False asserts that the specified value is false.
@@ -834,7 +827,6 @@ func False(t TestingT, value bool, msgAndArgs ...interface{}) bool {
 	}
 
 	return true
-
 }
 
 // NotEqual asserts that the specified values are NOT equal.
@@ -857,7 +849,6 @@ func NotEqual(t TestingT, expected, actual interface{}, msgAndArgs ...interface{
 	}
 
 	return true
-
 }
 
 // NotEqualValues asserts that two objects are not equal even when converted to the same type
@@ -880,7 +871,6 @@ func NotEqualValues(t TestingT, expected, actual interface{}, msgAndArgs ...inte
 // return (true, false) if element was not found.
 // return (true, true) if element was found.
 func containsElement(list interface{}, element interface{}) (ok, found bool) {
-
 	listValue := reflect.ValueOf(list)
 	listType := reflect.TypeOf(list)
 	if listType == nil {
@@ -915,7 +905,6 @@ func containsElement(list interface{}, element interface{}) (ok, found bool) {
 		}
 	}
 	return true, false
-
 }
 
 // Contains asserts that the specified string, list(array, slice...) or map contains the
@@ -938,7 +927,6 @@ func Contains(t TestingT, s, contains interface{}, msgAndArgs ...interface{}) bo
 	}
 
 	return true
-
 }
 
 // NotContains asserts that the specified string, list(array, slice...) or map does NOT contain the
@@ -961,7 +949,6 @@ func NotContains(t TestingT, s, contains interface{}, msgAndArgs ...interface{})
 	}
 
 	return true
-
 }
 
 // Subset asserts that the specified list(array, slice...) or map contains all
@@ -1667,7 +1654,6 @@ func matchRegexp(rx interface{}, str interface{}) bool {
 	default:
 		return r.MatchString(fmt.Sprint(v))
 	}
-
 }
 
 // Regexp asserts that a specified regexp matches a string.
@@ -1703,7 +1689,6 @@ func NotRegexp(t TestingT, rx interface{}, str interface{}, msgAndArgs ...interf
 	}
 
 	return !match
-
 }
 
 // Zero asserts that i is the zero value for its type.
@@ -1821,6 +1806,52 @@ func JSONEq(t TestingT, expected string, actual string, msgAndArgs ...interface{
 	return Equal(t, expectedJSONAsInterface, actualJSONAsInterface, msgAndArgs...)
 }
 
+type ValueMatchers = jsonmatch.Matchers
+
+// JSONMatchesBy asserts that two JSON strings are equivalent using one or more custom JSON matchers.
+// the value passed into the matcher will be on of the following types:
+// - string
+// - float64
+// - bool
+// - nil
+// - []interface{}
+// - map[string]interface{}
+//
+// Can use nil for matchers to test equality of pure json.
+//
+// Note: in cases where expected and actual are not equal, the value for the matcher will be displayed as unequal, 
+// regardless of the output of the matcher function.  This should be fixed in a future release.
+//
+//	assert.JSONMatchesBy(t, `{ "foo": "$NOT_EMPTY" }`, `{ "foo": "baz" }`, assert.ValueMatchers{
+//	    "$NOT_EMPTY": func(v interface) bool { return v != "" },
+//	})
+func JSONMatchesBy(t TestingT, expected string, actual string, matchers ValueMatchers, msgAndArgs ...interface{}) bool {
+	if h, ok := t.(tHelper); ok {
+		h.Helper()
+	}
+
+	var expectedJSONAsInterface, actualJSONAsInterface interface{}
+
+	if err := json.Unmarshal([]byte(expected), &expectedJSONAsInterface); err != nil {
+		return Fail(t, fmt.Sprintf("Expected value ('%s') is not valid json.\nJSON parsing error: '%s'", expected, err.Error()), msgAndArgs...)
+	}
+
+	if err := json.Unmarshal([]byte(actual), &actualJSONAsInterface); err != nil {
+		return Fail(t, fmt.Sprintf("Input ('%s') needs to be valid json.\nJSON parsing error: '%s'", actual, err.Error()), msgAndArgs...)
+	}
+
+	if !jsonmatch.MatchesBy(expectedJSONAsInterface, actualJSONAsInterface, matchers) {
+		diff := diff(expectedJSONAsInterface, actualJSONAsInterface)
+		expected, actual = formatUnequalValues(expectedJSONAsInterface, actualJSONAsInterface)
+		return Fail(t, fmt.Sprintf("Not equal: \n"+
+			"expected: %s\n"+
+			"actual  : %s%s", expectedJSONAsInterface, actualJSONAsInterface, diff), msgAndArgs...)
+
+	}
+
+	return true
+}
+
 // YAMLEq asserts that two YAML strings are equivalent.
 func YAMLEq(t TestingT, expected string, actual string, msgAndArgs ...interface{}) bool {
 	if h, ok := t.(tHelper); ok {