Add syntax.allowUnbalancedLoops option

CHANGELOG.md

@@ -1,3 +1,39 @@
+### 3.58.4
+
+Make it possible to write unbalanced loops, if specifying the following the option :
+
+```js
+const expressionParser = require("docxtemplater/expressions.js");
+const doc = new Docxtemplater(zip, {
+  paragraphLoop: true,
+  linebreaks: true,
+  syntax: {
+    allowUnbalancedLoops: true,
+  },
+});
+doc.render(/* data */);
+```
+
+Then the following template in a table will work
+
+```docx
+-------------------------
+| {#a}   | {/a}{#b}{/b} |
+-------------------------
+```
+
+This template will normally throw an "unbalanced_loop_tags" exception.
+
+The correct fix is to move the {#b} to be inside the {#a} loop like this :
+
+```docx
+-------------------------
+| {#a}   | {#b}{/b}{/a} |
+-------------------------
+```
+
+However, if you have some templates that were used before v3.19.9 of docxtemplater, and can't change the templates, you can use the `allowUnbalancedLoops` option.
+
 ### 3.58.3
 
 Do not throw an error if sending xml invalid character such as "\u0002" when using TxtTemplater.

es6/modules/expand-pair-trait.js

@@ -161,9 +161,13 @@ class ExpandPairTrait {
 			if (!expandTo || fileType === "text") {
 				const left = pair[0].offset;
 				const right = pair[1].offset;
-				if (left < lastRight) {
+				if (
+					left < lastRight &&
+					!this.docxtemplater.options.syntax.allowUnbalancedLoops
+				) {
 					errors.push(getUnbalancedLoopException(pair, lastPair));
 				}
+
 				lastPair = pair;
 				lastRight = right;
 				return [left, right];
@@ -179,7 +183,10 @@ class ExpandPairTrait {
 			} catch (e) {
 				errors.push(e);
 			}
-			if (left < lastRight) {
+			if (
+				left < lastRight &&
+				!this.docxtemplater.options.syntax.allowUnbalancedLoops
+			) {
 				errors.push(getUnbalancedLoopException(pair, lastPair));
 			}
 			lastRight = right;
@@ -192,7 +199,6 @@ class ExpandPairTrait {
 			return { postparsed, errors };
 		}
 		// Stryker restore all
-
 		let currentPairIndex = 0;
 		let innerParts;
 
@@ -207,20 +213,35 @@ class ExpandPairTrait {
 				newParsed.push(part);
 				return newParsed;
 			}
+			// We're inside the pair
 			if (expandedPair[0] === i) {
+				// Start pair
 				innerParts = [];
 			}
 			if (pair[0].offset !== i && pair[1].offset !== i) {
+				// Exclude inner pair indexes
 				innerParts.push(part);
 			}
 			if (expandedPair[1] === i) {
+				// End pair
 				const basePart = postparsed[pair[0].offset];
 				basePart.subparsed = postparse(innerParts, { basePart });
 				basePart.endLindex = pair[1].part.lIndex;
 				delete basePart.location;
 				delete basePart.expandTo;
 				newParsed.push(basePart);
 				currentPairIndex++;
+				let expandedPair = expandedPairs[currentPairIndex];
+				while (expandedPair && expandedPair[0] < i) {
+					/*
+					 * If we have :
+					 * expandedPairs =[[5,72],[51,67],[90,106]]
+					 * Then after treating [5,72], we need to treat [90,106]
+					 * Fixed since v3.58.4
+					 */
+					currentPairIndex++;
+					expandedPair = expandedPairs[currentPairIndex];
+				}
 			}
 			return newParsed;
 		}, []);

es6/tests/e2e/integration.js

@@ -1353,3 +1353,40 @@ describe("OptionsTransformer", () => {
 		);
 	});
 });
+
+describe("Syntax.allowUnbalancedLoops option", () => {
+	it("should work with unbalanced loop with allowUnbalancedLoops option", () => {
+		const doc = createDocV4("table-unbalanced-loop.docx", {
+			syntax: {
+				allowUnbalancedLoops: true,
+			},
+		});
+		doc.render({
+			a: [1, 2, 3],
+			b: [1, 2, 3],
+			c: [1, 2, 3],
+		});
+		shouldBeSame({
+			doc,
+			expectedName: "expected-table-unbalanced-loop.docx",
+		});
+	});
+
+	it("should work with unbalanced loop with allowUnbalancedLoops option (2)", () => {
+		const doc = createDocV4("table-unbalanced-loop-2.docx", {
+			syntax: {
+				allowUnbalancedLoops: true,
+			},
+		});
+
+		doc.render({
+			a: [1, 2, 3],
+			b: [1, 2, 3],
+			c: [1, 2, 3],
+		});
+		shouldBeSame({
+			doc,
+			expectedName: "expected-table-unbalanced-loop-2.docx",
+		});
+	});
+});