chore: add test for RenderScriptItems

README.md

@@ -74,6 +74,8 @@ go test -cover ./... -args -test.gocoverdir="$PWD/coverage/unit"
 go tool covdata percent -i=./coverage/generate,./coverage/unit
 # Generate a text coverage profile for tooling to use.
 go tool covdata textfmt -i=./coverage/generate,./coverage/unit -o coverage.out
+# Print total
+go tool cover -func coverage.out | grep total
 ```
 
 ### benchmark

runtime_test.go

@@ -494,3 +494,82 @@ func TestHandler(t *testing.T) {
 		})
 	}
 }
+
+func TestRenderScriptItems(t *testing.T) {
+	s1 := templ.ComponentScript{
+		Name:     "s1",
+		Function: "function s1() { return 'hello1'; }",
+	}
+	s2 := templ.ComponentScript{
+		Name:     "s2",
+		Function: "function s2() { return 'hello2'; }",
+	}
+	tests := []struct {
+		name     string
+		toIgnore []templ.ComponentScript
+		toRender []templ.ComponentScript
+		expected string
+	}{
+		{
+			name:     "if none are ignored, everything is rendered",
+			toIgnore: nil,
+			toRender: []templ.ComponentScript{s1, s2},
+			expected: `<script type="text/javascript">` + s1.Function + s2.Function + `</script>`,
+		},
+		{
+			name: "if something outside the expected is ignored, if has no effect",
+			toIgnore: []templ.ComponentScript{
+				{
+					Name:     "s3",
+					Function: "function s3() { return 'hello3'; }",
+				},
+			},
+			toRender: []templ.ComponentScript{s1, s2},
+			expected: `<script type="text/javascript">` + s1.Function + s2.Function + `</script>`,
+		},
+		{
+			name:     "if one is ignored, it's not rendered",
+			toIgnore: []templ.ComponentScript{s1},
+			toRender: []templ.ComponentScript{s1, s2},
+			expected: `<script type="text/javascript">` + s2.Function + `</script>`,
+		},
+		{
+			name: "if all are ignored, not even style tags are rendered",
+			toIgnore: []templ.ComponentScript{
+				s1,
+				s2,
+				{
+					Name:     "s3",
+					Function: "function s3() { return 'hello3'; }",
+				},
+			},
+			toRender: []templ.ComponentScript{s1, s2},
+			expected: ``,
+		},
+	}
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			ctx := context.Background()
+			b := new(bytes.Buffer)
+
+			// Render twice, reusing the same context so that there's a memory of which classes have been rendered.
+			ctx = templ.InitializeContext(ctx)
+			err := templ.RenderScriptItems(ctx, b, tt.toIgnore...)
+			if err != nil {
+				t.Fatalf("failed to render initial scripts: %v", err)
+			}
+
+			// Now render again to check that only the expected classes were rendered.
+			b.Reset()
+			err = templ.RenderScriptItems(ctx, b, tt.toRender...)
+			if err != nil {
+				t.Fatalf("failed to render scripts: %v", err)
+			}
+
+			if diff := cmp.Diff(tt.expected, b.String()); diff != "" {
+				t.Error(diff)
+			}
+		})
+	}
+}