Add compilation variables report option to allow getting all variables (even undeclared or internal) (#6192)

SomaticIT · web-flow · commit aedf69c1cf34 · 2021-06-29T09:43:52.000+08:00
* feat: add compilation variables report option

* test: add full var report test

* docs: document varsReport compile option
diff --git a/site/content/docs/04-compile-time.md b/site/content/docs/04-compile-time.md
@@ -44,7 +44,8 @@ The following options can be passed to the compiler. None are required:
 | `filename` | string | `null`
 | `name` | string | `"Component"`
 | `format` | `"esm"` or `"cjs"` | `"esm"`
-| `generate` | `"dom"` or `"ssr"` | `"dom"`
+| `generate` | `"dom"` or `"ssr" or false` | `"dom"`
+| `varsReport` | `"strict"` or `"full" or false` | `"strict"`
 | `dev` | boolean | `false`
 | `immutable` | boolean | `false`
 | `hydratable` | boolean | `false`
@@ -66,6 +67,7 @@ The following options can be passed to the compiler. None are required:
 | `name` | `"Component"` | `string` that sets the name of the resulting JavaScript class (though the compiler will rename it if it would otherwise conflict with other variables in scope). It will normally be inferred from `filename`.
 | `format` | `"esm"` | If `"esm"`, creates a JavaScript module (with `import` and `export`). If `"cjs"`, creates a CommonJS module (with `require` and `module.exports`), which is useful in some server-side rendering situations or for testing.
 | `generate` | `"dom"` | If `"dom"`, Svelte emits a JavaScript class for mounting to the DOM. If `"ssr"`, Svelte emits an object with a `render` method suitable for server-side rendering. If `false`, no JavaScript or CSS is returned; just metadata.
+| `varsReport` | `"strict"` | If `"strict"`, Svelte returns a variables report with only variables that are not globals nor internals. If `"full"`, Svelte returns a variables report with all detected variables. If `false`, no variables report is returned.
 | `dev` | `false` | If `true`, causes extra code to be added to components that will perform runtime checks and provide debugging information during development.
 | `immutable` | `false` | If `true`, tells the compiler that you promise not to mutate any objects. This allows it to be less conservative about checking whether values have changed.
 | `hydratable` | `false` | If `true` when generating DOM code, enables the `hydrate: true` runtime option, which allows a component to upgrade existing DOM rather than creating new DOM from scratch. When generating SSR code, this adds markers to `<head>` elements so that hydration knows which to replace.
diff --git a/src/compiler/compile/Component.ts b/src/compiler/compile/Component.ts
@@ -183,9 +183,12 @@ export default class Component {
 		this.stylesheet.warn_on_unused_selectors(this);
 	}
 
-	add_var(variable: Var) {
+	add_var(variable: Var, add_to_lookup = true) {
 		this.vars.push(variable);
-		this.var_lookup.set(variable.name, variable);
+
+		if (add_to_lookup) {
+			this.var_lookup.set(variable.name, variable);
+		}
 	}
 
 	add_reference(name: string) {
@@ -216,6 +219,10 @@ export default class Component {
 				variable.subscribable = true;
 			}
 		} else {
+			if (this.compile_options.varsReport === 'full') {
+				this.add_var({ name, referenced: true }, false);
+			}
+
 			this.used_names.add(name);
 		}
 	}
@@ -340,19 +347,7 @@ export default class Component {
 			css,
 			ast: this.original_ast,
 			warnings: this.warnings,
-			vars: this.vars
-				.filter(v => !v.global && !v.internal)
-				.map(v => ({
-					name: v.name,
-					export_name: v.export_name || null,
-					injected: v.injected || false,
-					module: v.module || false,
-					mutated: v.mutated || false,
-					reassigned: v.reassigned || false,
-					referenced: v.referenced || false,
-					writable: v.writable || false,
-					referenced_from_script: v.referenced_from_script || false
-				})),
+			vars: this.get_vars_report(),
 			stats: this.stats.render()
 		};
 	}
@@ -402,6 +397,28 @@ export default class Component {
 		};
 	}
 
+	get_vars_report(): Var[] {
+		const { compile_options, vars } = this;
+
+		const vars_report = compile_options.varsReport === false
+			? []
+			: compile_options.varsReport === 'full'
+				? vars
+				: vars.filter(v => !v.global && !v.internal);
+
+		return vars_report.map(v => ({
+			name: v.name,
+			export_name: v.export_name || null,
+			injected: v.injected || false,
+			module: v.module || false,
+			mutated: v.mutated || false,
+			reassigned: v.reassigned || false,
+			referenced: v.referenced || false,
+			writable: v.writable || false,
+			referenced_from_script: v.referenced_from_script || false
+		}));
+	}
+
 	error(
 		pos: {
 			start: number;
diff --git a/src/compiler/compile/index.ts b/src/compiler/compile/index.ts
@@ -14,6 +14,7 @@ const valid_options = [
 	'filename',
 	'sourcemap',
 	'generate',
+	'varsReport',
 	'outputFilename',
 	'cssOutputFilename',
 	'sveltePath',
diff --git a/src/compiler/interfaces.ts b/src/compiler/interfaces.ts
@@ -116,6 +116,7 @@ export interface CompileOptions {
 	name?: string;
 	filename?: string;
 	generate?: 'dom' | 'ssr' | false;
+	varsReport?: 'full' | 'strict' | false;
 
 	sourcemap?: object | string;
 	outputFilename?: string;
diff --git a/test/vars/samples/vars-report-false/_config.js b/test/vars/samples/vars-report-false/_config.js
@@ -0,0 +1,9 @@
+export default {
+	options: {
+		varsReport: false
+	},
+
+	test(assert, vars) {
+		assert.deepEqual(vars, []);
+	}
+};
diff --git a/test/vars/samples/vars-report-false/input.svelte b/test/vars/samples/vars-report-false/input.svelte
@@ -0,0 +1,5 @@
+<script>
+    export let foo = "bar";
+</script>
+
+{foo}
diff --git a/test/vars/samples/vars-report-full-noscript/_config.js b/test/vars/samples/vars-report-full-noscript/_config.js
@@ -0,0 +1,19 @@
+export default {
+	options: {
+		varsReport: 'full'
+	},
+
+	test(assert, vars) {
+		assert.deepEqual(vars, [{
+			name: 'foo',
+			export_name: null,
+			injected: false,
+			module: false,
+			mutated: false,
+			reassigned: false,
+			referenced: true,
+			referenced_from_script: false,
+			writable: false
+		}]);
+	}
+};
diff --git a/test/vars/samples/vars-report-full-noscript/input.svelte b/test/vars/samples/vars-report-full-noscript/input.svelte
@@ -0,0 +1 @@
+{foo}
diff --git a/test/vars/samples/vars-report-full-script/_config.js b/test/vars/samples/vars-report-full-script/_config.js
@@ -0,0 +1,31 @@
+export default {
+	options: {
+		varsReport: 'full'
+	},
+
+	test(assert, vars) {
+		assert.deepEqual(vars, [
+			{
+				name: 'foo',
+				export_name: 'foo',
+				injected: false,
+				module: false,
+				mutated: false,
+				reassigned: false,
+				referenced: true,
+				referenced_from_script: false,
+				writable: true
+			}, {
+				name: 'bar',
+				export_name: null,
+				injected: false,
+				module: false,
+				mutated: false,
+				reassigned: false,
+				referenced: true,
+				referenced_from_script: false,
+				writable: false
+			}
+		]);
+	}
+};
diff --git a/test/vars/samples/vars-report-full-script/input.svelte b/test/vars/samples/vars-report-full-script/input.svelte
@@ -0,0 +1,5 @@
+<script>
+    export let foo = "bar";
+</script>
+
+{foo} {bar}
diff --git a/test/vars/samples/vars-report-full/_config.js b/test/vars/samples/vars-report-full/_config.js
@@ -0,0 +1,19 @@
+export default {
+	options: {
+		varsReport: 'full'
+	},
+
+	test(assert, vars) {
+		assert.deepEqual(vars, [{
+			name: 'foo',
+			export_name: null,
+			injected: false,
+			module: false,
+			mutated: false,
+			reassigned: false,
+			referenced: true,
+			referenced_from_script: false,
+			writable: false
+		}]);
+	}
+};
diff --git a/test/vars/samples/vars-report-full/input.svelte b/test/vars/samples/vars-report-full/input.svelte
@@ -0,0 +1,3 @@
+<script></script>
+
+{foo}
