Reserved page sub-properties to allow new keys in page to be create…

…d downstream (page.excerpt or page.lang). Fixes #1173
11ty · Apr 13, 2024 · 2647b94 · 2647b94
1 parent 70df967
commit 2647b94
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Showing 4 changed files with 100 additions and 47 deletions.
diff --git a/src/Template.js b/src/Template.js
@@ -32,7 +32,6 @@ const debug = debugUtil("Eleventy:Template");
 const debugDev = debugUtil("Dev:Eleventy:Template");
 
 class EleventyTransformError extends EleventyBaseError {}
-class EleventyReservedDataError extends TypeError {}
 
 class Template extends TemplateContent {
 	constructor(templatePath, templateData, extensionMap, config) {
@@ -332,7 +331,7 @@ class Template extends TemplateContent {
 			debugDev("%o getData getTemplateDirectoryData and getGlobalData", this.inputPath);
 		}
 
-		let { data: frontMatterData, excerpt } = await this.getFrontMatterData();
+		let { data: frontMatterData } = await this.getFrontMatterData();
 		let layoutKey =
 			frontMatterData[this.config.keys.layout] ||
 			localData[this.config.keys.layout] ||
@@ -357,26 +356,20 @@ class Template extends TemplateContent {
 				frontMatterData,
 			);
 
-			let reserved = this.config.freezeReservedData ? ReservedData.getReservedKeys(mergedData) : [];
-			if (reserved.length > 0) {
-				let e = new EleventyReservedDataError(
-					`Cannot override reserved Eleventy properties: ${reserved.join(", ")}`,
-				);
-				e.reservedNames = reserved;
-				throw e;
+			if (this.config.freezeReservedData) {
+				ReservedData.check(mergedData);
 			}
 
-			this.addExcerpt(mergedData, excerpt);
-			mergedData = await this.addPageDate(mergedData);
-			mergedData = this.addPageData(mergedData);
+			await this.addPage(mergedData);
+
 			debugDev("%o getData mergedData", this.inputPath);
 
 			this._dataCache = mergedData;
 
 			return mergedData;
 		} catch (e) {
 			if (
-				e instanceof EleventyReservedDataError ||
+				ReservedData.isReservedDataError(e) ||
 				(e instanceof TypeError &&
 					e.message.startsWith("Cannot add property") &&
 					e.message.endsWith("not extensible"))
@@ -390,40 +383,25 @@ class Template extends TemplateContent {
 		}
 	}
 
-	async addPageDate(data) {
+	async addPage(data) {
 		if (!("page" in data)) {
 			data.page = {};
 		}
 
 		let newDate = await this.getMappedDate(data);
 
-		if ("page" in data && "date" in data.page) {
-			debug(
-				"Warning: data.page.date is in use (%o) will be overwritten with: %o",
-				data.page.date,
-				newDate,
-			);
-		}
-
 		data.page.date = newDate;
-
-		return data;
-	}
-
-	addPageData(data) {
-		if (!("page" in data)) {
-			data.page = {};
-		}
-
 		data.page.inputPath = this.inputPath;
 		data.page.fileSlug = this.fileSlugStr;
 		data.page.filePathStem = this.filePathStem;
 		data.page.outputFileExtension = this.engine.defaultTemplateFileExtension;
 		data.page.templateSyntax = this.templateRender.getEnginesList(
 			data[this.config.keys.engineOverride],
 		);
-
-		return data;
+		// data.page.url
+		// data.page.outputPath
+		// data.page.excerpt from gray-matter and Front Matter
+		// data.page.lang from I18nPlugin
 	}
 
 	// Tests only
@@ -573,6 +551,11 @@ class Template extends TemplateContent {
 				this,
 			);
 
+			// Check for reserved properties in computed data
+			if (this.config.freezeReservedData) {
+				ReservedData.check(data[this.config.keys.computed]);
+			}
+
 			// actually add the computed data
 			this._addComputedEntry(this.computedData, data[this.config.keys.computed]);
 

diff --git a/src/TemplateContent.js b/src/TemplateContent.js
@@ -180,16 +180,6 @@ class TemplateContent {
 		return this.config.virtualTemplates[inputDirRelativeInputPath];
 	}
 
-	addExcerpt(data, excerpt) {
-		if (!data || !excerpt) {
-			return;
-		}
-
-		// alias, defaults to page.excerpt
-		let alias = this.config.frontMatterParsingOptions?.excerpt_alias || "page.excerpt";
-		lodashSet(data, alias, excerpt);
-	}
-
 	async read() {
 		if (!this.readingPromise) {
 			if (!this.inputContent) {
@@ -232,8 +222,8 @@ class TemplateContent {
 							}
 
 							// alias, defaults to page.excerpt
-							// let alias = options.excerpt_alias || "page.excerpt";
-							// lodashSet(fm.data, alias, fm.excerpt);
+							let alias = options.excerpt_alias || "page.excerpt";
+							lodashSet(fm.data, alias, fm.excerpt);
 						}
 
 						// For monkey patchers that used `frontMatter` 🤧

diff --git a/src/Util/ReservedData.js b/src/Util/ReservedData.js
@@ -1,10 +1,64 @@
+class EleventyReservedDataError extends TypeError {}
+
 class ReservedData {
-	static properties = ["page", "content", "collections"];
+	static properties = [
+		// "pkg", // Object.freeze’d upstream
+		// "eleventy", // Object.freeze’d upstream
+		// "page" is only frozen for specific subproperties below
+		"content",
+		"collections",
+	];
+
+	static pageProperties = [
+		"date",
+		"inputPath",
+		"fileSlug",
+		"filePathStem",
+		"outputFileExtension",
+		"templateSyntax",
+		"url",
+		"outputPath",
+		// not yet `excerpt` or `lang` set via front matter and computed data
+	];
 
+	// Check in the data cascade for reserved data properties.
 	static getReservedKeys(data) {
-		return this.properties.filter((key) => {
+		let keys = this.properties.filter((key) => {
 			return key in data;
 		});
+
+		if ("page" in data) {
+			if (typeof data.page === "object") {
+				for (let key of this.pageProperties) {
+					if (key in data.page) {
+						keys.push(`page.${key}`);
+					}
+				}
+			} else {
+				// fail `page` when set to non-object values.
+				keys.push("page");
+			}
+		}
+		return keys;
+	}
+
+	static check(data) {
+		let reserved = ReservedData.getReservedKeys(data);
+		if (reserved.length === 0) {
+			return;
+		}
+
+		let error = new EleventyReservedDataError(
+			`Cannot override reserved Eleventy properties: ${reserved.join(", ")}`,
+		);
+
+		error.reservedNames = reserved;
+
+		throw error;
+	}
+
+	static isReservedDataError(e) {
+		return e instanceof EleventyReservedDataError;
 	}
 }
 

diff --git a/test/ReservedDataTest.js b/test/ReservedDataTest.js
@@ -0,0 +1,26 @@
+import test from "ava";
+import ReservedData from "../src/Util/ReservedData.js";
+
+test("No reserved Keys", t => {
+  t.deepEqual(ReservedData.getReservedKeys({ key: {} }).sort(), []);
+});
+
+test("Standard keys are reserved", t => {
+  t.deepEqual(ReservedData.getReservedKeys({ content: "" }).sort(), ["content"]);
+  t.deepEqual(ReservedData.getReservedKeys({ collections: {} }).sort(), ["collections"]);
+  t.deepEqual(ReservedData.getReservedKeys({ content: "", collections: {} }).sort(), ["collections", "content"]);
+});
+
+test("`page` subkeys", t => {
+  t.deepEqual(ReservedData.getReservedKeys({ page: {} }).sort(), []);
+  t.deepEqual(ReservedData.getReservedKeys({ page: "" }).sort(), ["page"]);
+  t.deepEqual(ReservedData.getReservedKeys({ page: { date: "", otherkey: "" } }).sort(), ["page.date"]);
+  t.deepEqual(ReservedData.getReservedKeys({ page: { inputPath: "", otherkey: "" } }).sort(), ["page.inputPath"]);
+  t.deepEqual(ReservedData.getReservedKeys({ page: { fileSlug: "", otherkey: "" } }).sort(), ["page.fileSlug"]);
+  t.deepEqual(ReservedData.getReservedKeys({ page: { filePathStem: "", otherkey: "" } }).sort(), ["page.filePathStem"]);
+  t.deepEqual(ReservedData.getReservedKeys({ page: { outputFileExtension: "", otherkey: "" } }).sort(), ["page.outputFileExtension"]);
+  t.deepEqual(ReservedData.getReservedKeys({ page: { templateSyntax: "", otherkey: "" } }).sort(), ["page.templateSyntax"]);
+  t.deepEqual(ReservedData.getReservedKeys({ page: { url: "", otherkey: "" } }).sort(), ["page.url"]);
+  t.deepEqual(ReservedData.getReservedKeys({ page: { outputPath: "", otherkey: "" } }).sort(), ["page.outputPath"]);
+  t.deepEqual(ReservedData.getReservedKeys({ page: { date: "", outputPath: "", otherkey: "" } }).sort(), ["page.date", "page.outputPath"]);
+});