From 06bed7e59a5814d2898d5133ded1e53ca9fcc4d4 Mon Sep 17 00:00:00 2001
From: Jean-Yves Moyen <jym@siteimprove.com>
Date: Mon, 15 Jan 2024 11:36:51 +0100
Subject: [PATCH] Clean up

---
 .changeset/kind-singers-teach.md               |  8 ++++++++
 packages/alfa-cascade/src/block.ts             |  2 +-
 packages/alfa-cascade/src/precedence/origin.ts |  2 +-
 packages/alfa-cascade/test/rule-tree.spec.ts   | 12 ++++--------
 packages/alfa-style/src/variable.ts            |  8 +-------
 packages/alfa-style/test/style.spec.tsx        |  2 +-
 6 files changed, 16 insertions(+), 18 deletions(-)
 create mode 100644 .changeset/kind-singers-teach.md

diff --git a/.changeset/kind-singers-teach.md b/.changeset/kind-singers-teach.md
new file mode 100644
index 0000000000..83f6799101
--- /dev/null
+++ b/.changeset/kind-singers-teach.md
@@ -0,0 +1,8 @@
+---
+"@siteimprove/alfa-cascade": minor
+---
+
+**Added:** Cascade now handle importance of declarations, and `style` attribute.
+
+This should have no impact on regular usage of `Style.from()` but may affect code trying to use the cascade directly.
+Most notably, the internal rule tree `Block` can now come either from a rule or an element. Therefore, `Block.rule` and `Bolkc.selector` may now be `null`.
diff --git a/packages/alfa-cascade/src/block.ts b/packages/alfa-cascade/src/block.ts
index dc01ef663b..e524c8f863 100644
--- a/packages/alfa-cascade/src/block.ts
+++ b/packages/alfa-cascade/src/block.ts
@@ -256,7 +256,7 @@ export namespace Block {
 
   /**
    * Turns the style attribute of an element into blocks (one for important
-   * declaration, one for normal declarations).
+   * declarations, one for normal declarations).
    * @param element
    */
   export function fromStyle(element: Element): Iterable<Block> {
diff --git a/packages/alfa-cascade/src/precedence/origin.ts b/packages/alfa-cascade/src/precedence/origin.ts
index da8e3ff31f..564c523d15 100644
--- a/packages/alfa-cascade/src/precedence/origin.ts
+++ b/packages/alfa-cascade/src/precedence/origin.ts
@@ -10,7 +10,7 @@ import { Comparable, type Comparer } from "@siteimprove/alfa-comparable";
  * Mixing both here allows for the comparison to be simple number comparison,
  * which should be faster than looking at more than one field.
  *
- * Cascading origins defined in ascending order; origins defined first have
+ * Cascading origins are defined in ascending order; origins defined first have
  * lower precedence than origins defined later. Thus, an origin with higher
  * value takes precedence over an origin with lower value. This means that
  * comparing origins is the same as comparing numbers.
diff --git a/packages/alfa-cascade/test/rule-tree.spec.ts b/packages/alfa-cascade/test/rule-tree.spec.ts
index a398b33d09..d57f6457af 100644
--- a/packages/alfa-cascade/test/rule-tree.spec.ts
+++ b/packages/alfa-cascade/test/rule-tree.spec.ts
@@ -15,23 +15,19 @@ import { Block } from "../src/block";
 import { Origin } from "../src/precedence";
 
 function fakeBlock(
-  selector: string,
+  selectorText: string,
   origin: Origin = Origin.NormalUserAgent,
 ): Block {
-  const sel = parse(selector) as Compound | Complex | Simple;
+  const selector = parse(selectorText) as Compound | Complex | Simple;
 
-  return Block.of({ rule: h.rule.style(selector, []), selector: sel }, [], {
+  return Block.of({ rule: h.rule.style(selectorText, []), selector }, [], {
     origin,
     isElementAttached: false,
-    specificity: sel.specificity,
+    specificity: selector.specificity,
     order: -1,
   });
 }
 
-// function fakeJSON(selector: string, origin?: Origin): Block.JSON {
-//   return fakeBlock(selector, origin).toJSON();
-// }
-
 // Selectors `div`, `.foo`, `#bar`, matching, e.g., `<div class="foo" id="bar">`
 // and inserted in increasing specificity.
 const div = fakeBlock("div");
diff --git a/packages/alfa-style/src/variable.ts b/packages/alfa-style/src/variable.ts
index 9a8db46602..01c691f26c 100644
--- a/packages/alfa-style/src/variable.ts
+++ b/packages/alfa-style/src/variable.ts
@@ -34,13 +34,7 @@ export namespace Variable {
    * This builds a map from variable names to their lexed value
    * i.e. "--foo: lorem ipsum" becomes "foo => [lorem, ipsum]"
    **/
-  export function gather(
-    declarations: Array<Declaration>,
-    // shouldOverride: <T>(
-    //   previous: Option<Value<T>>,
-    //   next: Declaration,
-    // ) => boolean,
-  ): DefinitionMap {
+  export function gather(declarations: Array<Declaration>): DefinitionMap {
     let currentVariables: DefinitionMap = Map.empty();
 
     for (const declaration of declarations.filter((declaration) =>
diff --git a/packages/alfa-style/test/style.spec.tsx b/packages/alfa-style/test/style.spec.tsx
index 54010841af..e45cf42f7c 100644
--- a/packages/alfa-style/test/style.spec.tsx
+++ b/packages/alfa-style/test/style.spec.tsx
@@ -199,7 +199,7 @@ test(`#cascaded() expands a var() function`, (t) => {
   });
 });
 
-test("#cascaded() prefer important var() declarations", (t) => {
+test("#cascaded() prefers important var() declarations", (t) => {
   const element = <div class="foo" id="foo" />;
 
   h.document(