goradd · spekary · Dec 10, 2023 · Dec 10, 2023
diff --git a/.gitignore b/.gitignore
@@ -4,6 +4,8 @@
 *.dll
 *.so
 *.dylib
+.idea/
+.DS_Store
 
 # Test binary, built with `go test -c`
 *.test

diff --git a/attributes.go b/attributes.go
@@ -28,7 +28,8 @@ type Attributer interface {
 // and then convert it to a string to get the attributes embeddable in an HTML tag.
 //
 // To create new attributes, the easiest is to do this:
-//   a := Attributes{"id":"theId", "class":"myClass"}
+//
+//	a := Attributes{"id":"theId", "class":"myClass"}
 type Attributes map[string]string
 
 // NewAttributes creates a new Attributes collection.
@@ -350,7 +351,8 @@ func (a Attributes) Merge(aIn Attributes) Attributes {
 // OverrideString merges an attribute string into the attributes. Conflicts are won by the string.
 //
 // It takes an attribute string of the form
-//   a="b" c="d"
+//
+//	a="b" c="d"
 func (a Attributes) OverrideString(s string) Attributes {
 	if s == "" {
 		return a
@@ -364,7 +366,8 @@ func (a Attributes) OverrideString(s string) Attributes {
 // Conflicts are won by the string, but styles and classes merge.
 //
 // It takes an attribute string of the form
-//   a="b" c="d"
+//
+//	a="b" c="d"
 func (a Attributes) MergeString(s string) Attributes {
 	if s == "" {
 		return a
@@ -473,6 +476,15 @@ func (a Attributes) RemoveClassesWithPrefix(v string) bool {
 	return false
 }
 
+// HasClassWithPrefix returns true if the attribute has a class with the given prefix.
+func (a Attributes) HasClassWithPrefix(prefix string) bool {
+	if a.Has("class") {
+		class := a.Get("class")
+		return HasWordWithPrefix(class, prefix)
+	}
+	return false
+}
+
 // AddValuesChanged adds the given space separated values to the end of the values in the
 // given attribute, removing duplicates and returning true if the attribute was changed at all.
 // An example of a place to use this is the aria-labelledby attribute, which can take multiple
@@ -556,6 +568,7 @@ func (a Attributes) HasClass(c string) bool {
 //	<div id='test1' data-test-case="my test"></div>
 //
 // You would get that value in javascript by doing:
+//
 //	g$('test1').data('testCase');
 //
 // Conversion to special html data-* name formatting is handled here automatically. So if you SetData('testCase') here,
@@ -772,9 +785,9 @@ func getAttributesFromTemplate(s string) Attributes {
 /*
 type AttributeCreator map[string]string
 
-func (c AttributeCreator) Create() Attributes {
-	return Attributes(c)
-}
+	func (c AttributeCreator) Create() Attributes {
+		return Attributes(c)
+	}
 */
 var templateMatcher *regexp.Regexp
 

diff --git a/attributes_test.go b/attributes_test.go
@@ -394,6 +394,13 @@ func ExampleAttributes_RemoveClassesWithPrefix() {
 	// Output: class="that"
 }
 
+func ExampleAttributes_HasClassWithPrefix() {
+	a := Attributes{"class": "col-2 that"}
+	found := a.HasClassWithPrefix("col-")
+	fmt.Println(found)
+	// Output: true
+}
+
 func ExampleAttributes_AddValues() {
 	a := Attributes{"abc": "123"}
 	a.AddValues("abc", "456")

diff --git a/class.go b/class.go
@@ -94,3 +94,15 @@ func RemoveClassesWithPrefix(class string, prefix string) string {
 
 	return ret
 }
+
+// HasWordWithPrefix returns true if the given string has a word in it with the given prefix.
+func HasWordWithPrefix(class string, prefix string) bool {
+	classes := strings.Fields(class)
+
+	for _, s := range classes {
+		if strings.HasPrefix(s, prefix) {
+			return true
+		}
+	}
+	return false
+}
diff --git a/class_test.go b/class_test.go
@@ -30,6 +30,12 @@ func ExampleRemoveClassesWithPrefix() {
 	// Output: col4-other
 }
 
+func ExampleHasClassWithPrefix() {
+	exists := HasWordWithPrefix("col-6 col-brk col4-other", "col4-")
+	fmt.Println(exists)
+	// Output: true
+}
+
 func TestMergeWords1(t *testing.T) {
 	tests := []struct {
 		name           string
@@ -53,3 +59,25 @@ func TestMergeWords1(t *testing.T) {
 		})
 	}
 }
+
+func TestHasClassWithPrefix(t *testing.T) {
+	tests := []struct {
+		name   string
+		class  string
+		prefix string
+		want   bool
+	}{
+		{"True - one", "a-b c-d", "a-", true},
+		{"True - two", "a-b a-c c-d", "a-", true},
+		{"False - none", "", "a-", false},
+		{"False - one", "b-c", "a-", false},
+		{"False - two", "b-c c-d", "a-", false},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := HasWordWithPrefix(tt.class, tt.prefix); got != tt.want {
+				t.Errorf("HasWordWithPrefix() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
-Original file line number
+Diff line change
@@ Expand Up / @@ -4,6 +4,8 @@ @@
     *.dll
     *.so
     *.dylib
+    .idea/
+    .DS_Store
     # Test binary, built with `go test -c`
     *.test
@@ Expand Down @@