perf: save 0.2kB bundle size by const-ing error message (#21)

* perf: save 0.2kB bundle size by const-ing error message * i did run prettier this time * add tests * `throw new NotAllowedError` and improved error msg --------- Co-authored-by: Bart Veneman <[email protected]>
bramus · Feb 18, 2024 · 771a237 · 771a237
1 parent 5c84df3
commit 771a237
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Showing 2 changed files with 107 additions and 5 deletions.
diff --git a/src/index.js b/src/index.js
@@ -1,9 +1,15 @@
 import generate from 'css-tree/generator';
-
 import { calculate } from './core/index.js';
 import { compare, equals, greaterThan, lessThan } from './util/compare.js';
 import { min, max } from './util/filter.js';
 import { sortAsc, sortDesc } from './util/sort.js';
+
+class NotAllowedError extends Error {
+    constructor() {
+        super('Manipulating a Specificity instance is not allowed. Instead, create a new Specificity()');
+    }
+}
+
 class Specificity {
     constructor(value, selector = null) {
         this.value = value;
@@ -15,23 +21,23 @@ class Specificity {
     }
 
     set a(val) {
-        throw new Error('Manipulating the port of the specificity directly is not allowed. Instead, directly set a new value');
+        throw new NotAllowedError();
     }
 
     get b() {
         return this.value.b;
     }
 
     set b(val) {
-        throw new Error('Manipulating the port of the specificity directly is not allowed. Instead, directly set a new value');
+        throw new NotAllowedError();
     }
 
     get c() {
         return this.value.c;
     }
 
     set c(val) {
-        throw new Error('Manipulating the port of the specificity directly is not allowed. Instead, directly set a new value');
+        throw new NotAllowedError();
     }
 
     selectorString() {

diff --git a/test/types.js b/test/types.js
@@ -1,4 +1,4 @@
-import { deepEqual } from 'assert';
+import { deepEqual, throws } from 'assert';
 import Specificity from '../dist/index.js';
 
 describe('Specificity Class, manual instance', () => {
@@ -18,6 +18,38 @@ describe('Specificity Class, manual instance', () => {
             deepEqual(s.c, 3);
         });
     });
+    describe('Instance Setters', () => {
+        it('Specificity.a', () => {
+            throws(
+                () => {
+                    s.a = 1;
+                },
+                {
+                    message: 'Manipulating a Specificity instance is not allowed. Instead, create a new Specificity()',
+                }
+            );
+        });
+        it('Specificity.b', () => {
+            throws(
+                () => {
+                    s.b = 1;
+                },
+                {
+                    message: 'Manipulating a Specificity instance is not allowed. Instead, create a new Specificity()',
+                }
+            );
+        });
+        it('Specificity.c', () => {
+            throws(
+                () => {
+                    s.c = 1;
+                },
+                {
+                    message: 'Manipulating a Specificity instance is not allowed. Instead, create a new Specificity()',
+                }
+            );
+        });
+    });
     describe('Value Formatting', () => {
         it('Specificity.toString()', () => {
             deepEqual(s.toString(), '(1,2,3)');
@@ -59,6 +91,38 @@ describe('Specificity Class, manual instance, no given selector', () => {
             deepEqual(s.c, 3);
         });
     });
+    describe('Instance Setters', () => {
+        it('Specificity.a', () => {
+            throws(
+                () => {
+                    s.a = 1;
+                },
+                {
+                    message: 'Manipulating a Specificity instance is not allowed. Instead, create a new Specificity()',
+                }
+            );
+        });
+        it('Specificity.b', () => {
+            throws(
+                () => {
+                    s.b = 1;
+                },
+                {
+                    message: 'Manipulating a Specificity instance is not allowed. Instead, create a new Specificity()',
+                }
+            );
+        });
+        it('Specificity.c', () => {
+            throws(
+                () => {
+                    s.c = 1;
+                },
+                {
+                    message: 'Manipulating a Specificity instance is not allowed. Instead, create a new Specificity()',
+                }
+            );
+        });
+    });
     describe('Value Formatting', () => {
         it('Specificity.toString()', () => {
             deepEqual(s.toString(), '(1,2,3)');
@@ -100,6 +164,38 @@ describe('Specificity Class', () => {
             deepEqual(s.c, 3);
         });
     });
+    describe('Instance Setters', () => {
+        it('Specificity.a', () => {
+            throws(
+                () => {
+                    s.a = 1;
+                },
+                {
+                    message: 'Manipulating a Specificity instance is not allowed. Instead, create a new Specificity()',
+                }
+            );
+        });
+        it('Specificity.b', () => {
+            throws(
+                () => {
+                    s.b = 1;
+                },
+                {
+                    message: 'Manipulating a Specificity instance is not allowed. Instead, create a new Specificity()',
+                }
+            );
+        });
+        it('Specificity.c', () => {
+            throws(
+                () => {
+                    s.c = 1;
+                },
+                {
+                    message: 'Manipulating a Specificity instance is not allowed. Instead, create a new Specificity()',
+                }
+            );
+        });
+    });
     describe('Value Formatting', () => {
         it('Specificity.toString()', () => {
             deepEqual(s.toString(), '(1,2,3)');