Add keyword arguments for Liquid shortcodes

This is an adaptation of #1733 to use the built-in Liquid argument
parser that was added in #2679.

Co-Authored-By: Dylan Awalt-Conley <[email protected]>

Author: nex3

src/Engines/Liquid.js

@@ -172,20 +172,57 @@ class Liquid extends TemplateEngine {
 		let tokenizer = new Tokenizer(args);
 		let parsedArgs = [];
 
-		let value = tokenizer.readValue();
+		function readValue() {
+			let value = tokenizer.readHash() ?? tokenizer.readValue();
+			// readHash() treats unmarked identifiers as hash keys with undefined
+			// values, but we want to parse them as positional arguments instead.
+			return value?.kind === 64 && value.value === undefined ? value.name : value;
+		}
+
+		let value = readValue();
 		while (value) {
 			parsedArgs.push(value);
 			tokenizer.skipBlank();
 			if (tokenizer.peek() === ",") {
 				tokenizer.advance();
 			}
-			value = tokenizer.readValue();
+			value = readValue();
 		}
 		tokenizer.end();
 
 		return parsedArgs;
 	}
 
+	static *evalArguments(tag, ctx) {
+		let argArray = [];
+		let namedArgs = {};
+		if (tag.legacyArgs) {
+			let rawArgs = Liquid.parseArguments(_t.argLexer, tag.legacyArgs);
+			for (let arg of rawArgs) {
+				let b = yield liquidEngine.evalValue(arg, ctx);
+				argArray.push(b);
+			}
+		} else if (tag.orderedArgs) {
+			for (let arg of tag.orderedArgs) {
+				if (arg.kind == 64) {
+					if (arg.value === undefined) {
+						namedArgs[arg.name.content] = true;
+					} else {
+						namedArgs[arg.name.content] = yield evalToken(arg.value, ctx);
+					}
+				} else {
+					let b = yield evalToken(arg, ctx);
+					argArray.push(b);
+				}
+			}
+		}
+
+		if (Object.keys(namedArgs).length > 0) {
+			argArray.push(namedArgs);
+		}
+		return argArray;
+	}
+
 	addShortcode(shortcodeName, shortcodeFn) {
 		let _t = this;
 		this.addTag(shortcodeName, function (liquidEngine) {
@@ -200,21 +237,7 @@ class Liquid extends TemplateEngine {
 					}
 				},
 				render: function* (ctx) {
-					let argArray = [];
-
-					if (this.legacyArgs) {
-						let rawArgs = Liquid.parseArguments(_t.argLexer, this.legacyArgs);
-						for (let arg of rawArgs) {
-							let b = yield liquidEngine.evalValue(arg, ctx);
-							argArray.push(b);
-						}
-					} else if (this.orderedArgs) {
-						for (let arg of this.orderedArgs) {
-							let b = yield evalToken(arg, ctx);
-							argArray.push(b);
-						}
-					}
-
+					let argArray = yield* Liquid.evalArguments(this, ctx);
 					let ret = yield shortcodeFn.call(Liquid.normalizeScope(ctx), ...argArray);
 					return ret;
 				},
@@ -249,19 +272,7 @@ class Liquid extends TemplateEngine {
 					stream.start();
 				},
 				render: function* (ctx /*, emitter*/) {
-					let argArray = [];
-					if (this.legacyArgs) {
-						let rawArgs = Liquid.parseArguments(_t.argLexer, this.legacyArgs);
-						for (let arg of rawArgs) {
-							let b = yield liquidEngine.evalValue(arg, ctx);
-							argArray.push(b);
-						}
-					} else if (this.orderedArgs) {
-						for (let arg of this.orderedArgs) {
-							let b = yield evalToken(arg, ctx);
-							argArray.push(b);
-						}
-					}
+					let argArray = yield* Liquid.evalArguments(this, ctx);
 
 					const html = yield liquidEngine.renderer.renderTemplates(this.templates, ctx);
 

test/TemplateRenderLiquidTest.js

@@ -658,6 +658,38 @@ test("Liquid Nested Paired Shortcode", async (t) => {
   );
 });
 
+test("Liquid Paired Kwargs Shortcode with Tag Inside", async (t) => {
+  let tr = await getNewTemplateRender("liquid", "./test/stubs/");
+  tr.engine.addPairedShortcode("postfixWithZach", function (content, kwargs) {
+    var { str } = kwargs ?? {};
+    return str + content + "Zach";
+  });
+
+  t.is(
+    await tr._testRender(
+      "{% postfixWithZach str: name %}Content{% if tester %}If{% endif %}{% endpostfixWithZach %}",
+      { name: "test", tester: true }
+    ),
+    "testContentIfZach"
+  );
+});
+
+test("Liquid Nested Paired Kwargs Shortcode", async (t) => {
+  let tr = await getNewTemplateRender("liquid", "./test/stubs/");
+  tr.engine.addPairedShortcode("postfixWithZach", function (content, kwargs) {
+    var { str } = kwargs ?? {};
+    return str + content + "Zach";
+  });
+
+  t.is(
+    await tr._testRender(
+      "{% postfixWithZach str: name %}Content{% postfixWithZach str: name2 %}Content{% endpostfixWithZach %}{% endpostfixWithZach %}",
+      { name: "test", name2: "test2" }
+    ),
+    "testContenttest2ContentZachZach"
+  );
+});
+
 test("Liquid Shortcode Multiple Args", async (t) => {
   let tr = await getNewTemplateRender("liquid", "./test/stubs/");
   tr.engine.addShortcode("postfixWithZach", function (str, str2) {
@@ -673,6 +705,56 @@ test("Liquid Shortcode Multiple Args", async (t) => {
   );
 });
 
+test("Liquid Shortcode Keyword Arg", async (t) => {
+  let tr = await getNewTemplateRender("liquid", "./test/stubs/");
+  tr.engine.addShortcode("postfixWithZach", function (str, kwargs) {
+    let { append } = kwargs ?? {};
+    return str + "Zach" + append;
+  });
+
+  t.is(
+    await tr._testRender("{% postfixWithZach name append: other %}", {
+      name: "test",
+      other: "howdy",
+    }),
+    "testZachhowdy"
+  );
+});
+
+test("Liquid Shortcode Multiple Keyword Args", async (t) => {
+  let tr = await getNewTemplateRender("liquid", "./test/stubs/");
+  tr.engine.addShortcode("postfixWithZach", function (str, kwargs) {
+    let { prepend, append } = kwargs ?? {};
+    return prepend + str + "Zach" + append;
+  });
+
+  t.is(
+    await tr._testRender(
+      "{% postfixWithZach name prepend: 'string' append: other %}",
+      {
+        name: "test",
+        other: "howdy",
+      }
+    ),
+    "stringtestZachhowdy"
+  );
+});
+
+test("Liquid Shortcode Only Keyword Args", async (t) => {
+  let tr = await getNewTemplateRender("liquid", "./test/stubs/");
+  tr.engine.addShortcode("postfixWithZach", function (kwargs) {
+    let { prepend, append } = kwargs ?? {};
+    return prepend + "Zach" + append;
+  });
+
+  t.is(
+    await tr._testRender("{% postfixWithZach prepend: 'string' append: name %}", {
+      name: "test",
+    }),
+    "stringZachtest"
+  );
+});
+
 test("Liquid Include Scope Leak", async (t) => {
   let tr1 = await getNewTemplateRender("liquid", "./test/stubs/");
   t.is(tr1.getEngineName(), "liquid");