section is allowed only in document root

examples/sections.js

@@ -65,15 +65,15 @@ var docDefinition = {
 			pageOrientation: 'inherit',
 			pageMargins: 'inherit',
 			section: [
-				'SECTION 7',
+				'SECTION 6',
 				'Text in section with page definition as previous page. Page size, orientation and margins are inherited.'
 			]
 		},
 		{
 			header: function (currentPage, pageCount) { return 'header in section 8: ' + currentPage.toString() + ' of ' + pageCount; },
 			footer: function (currentPage, pageCount) { return 'footer in section 8: ' + currentPage.toString() + ' of ' + pageCount; },
 			section: [
-				'SECTION 8',
+				'SECTION 7',
 				'Text in section with page definition as defined in document.'
 			]
 		}

src/DocMeasure.js

@@ -34,6 +34,10 @@ class DocMeasure {
 		return this.measureNode(docStructure);
 	}
 
+	measureBlock(node) {
+		return this.measureNode(node);
+	}
+
 	measureNode(node) {
 		return this.styleStack.auto(node, () => {
 			// TODO: refactor + rethink whether this is the proper way to handle margins

src/DocPreprocessor.js

@@ -20,10 +20,17 @@ class DocPreprocessor {
 		this.parentNode = null;
 		this.tocs = [];
 		this.nodeReferences = [];
-		return this.preprocessNode(docStructure);
+		return this.preprocessNode(docStructure, true);
 	}
 
-	preprocessNode(node) {
+	preprocessBlock(node) {
+		this.parentNode = null;
+		this.tocs = [];
+		this.nodeReferences = [];
+		return this.preprocessNode(node);
+	}
+
+	preprocessNode(node, isSectionAllowed = false) {
 		// expand shortcuts and casting values
 		if (Array.isArray(node)) {
 			node = { stack: node };
@@ -34,12 +41,15 @@ class DocPreprocessor {
 		}
 
 		if (node.section) {
-			// TODO: add a check that section node is in root
+			if (!isSectionAllowed) {
+				throw new Error(`Incorrect document structure, section node is only allowed at the root level of document structure: ${stringifyNode(node)}`);
+			}
+
 			return this.preprocessSection(node);
 		} else if (node.columns) {
 			return this.preprocessColumns(node);
 		} else if (node.stack) {
-			return this.preprocessVerticalContainer(node);
+			return this.preprocessVerticalContainer(node, isSectionAllowed);
 		} else if (node.ul) {
 			return this.preprocessList(node);
 		} else if (node.ol) {
@@ -83,11 +93,11 @@ class DocPreprocessor {
 		return node;
 	}
 
-	preprocessVerticalContainer(node) {
+	preprocessVerticalContainer(node, isSectionAllowed) {
 		let items = node.stack;
 
 		for (let i = 0, l = items.length; i < l; i++) {
-			items[i] = this.preprocessNode(items[i]);
+			items[i] = this.preprocessNode(items[i], isSectionAllowed);
 		}
 
 		return node;

src/LayoutBuilder.js

@@ -218,8 +218,8 @@ class LayoutBuilder {
 
 		if (pageBackground) {
 			this.writer.beginUnbreakableBlock(pageSize.width, pageSize.height);
-			pageBackground = this.docPreprocessor.preprocessDocument(pageBackground);
-			this.processNode(this.docMeasure.measureDocument(pageBackground));
+			pageBackground = this.docPreprocessor.preprocessBlock(pageBackground);
+			this.processNode(this.docMeasure.measureBlock(pageBackground));
 			this.writer.commitUnbreakableBlock(0, 0);
 			context.backgroundLength[context.page] += pageBackground.positions.length;
 		}
@@ -247,8 +247,8 @@ class LayoutBuilder {
 			if (node) {
 				let sizes = sizeFunction(this.writer.context().getCurrentPage().pageSize, this.writer.context().getCurrentPage().pageMargins);
 				this.writer.beginUnbreakableBlock(sizes.width, sizes.height);
-				node = this.docPreprocessor.preprocessDocument(node);
-				this.processNode(this.docMeasure.measureDocument(node));
+				node = this.docPreprocessor.preprocessBlock(node);
+				this.processNode(this.docMeasure.measureBlock(node));
 				this.writer.commitUnbreakableBlock(sizes.x, sizes.y);
 			}
 		}

tests/unit/DocPreprocessor.spec.js

@@ -1,4 +1,3 @@
-
 const assert = require('assert');
 
 const DocPreprocessor = require('../../js/DocPreprocessor').default;
@@ -79,28 +78,28 @@ describe('DocPreprocessor', function () {
 
 		it('should normalize text', function () {
 			var ddContent = [
-				{ text: 'Abc123' },
-				{ text: '12' },
-				{ text: '12.34' },
-				{ text: '0' },
-				{ text: '' },
-				{ text: new String('Abcdef') },
-				{ text: 56 },
-				{ text: 56.78 },
-				{ text: 0 },
-				{ text: true },
-				{ text: false },
-				{ text: 'true' },
-				{ text: 'false' },
-				{ text: [] }, // is text with nested texts
-				{ text: '[]' },
-				{ text: [1, 2, 3] }, // is text with nested texts
-				{ text: {} },
-				{ text: '{}' },
-				{ text: null },
-				{ text: 'null' },
-				{ text: undefined },
-				{ text: 'undefined' },
+				{text: 'Abc123'},
+				{text: '12'},
+				{text: '12.34'},
+				{text: '0'},
+				{text: ''},
+				{text: new String('Abcdef')},
+				{text: 56},
+				{text: 56.78},
+				{text: 0},
+				{text: true},
+				{text: false},
+				{text: 'true'},
+				{text: 'false'},
+				{text: []}, // is text with nested texts
+				{text: '[]'},
+				{text: [1, 2, 3]}, // is text with nested texts
+				{text: {}},
+				{text: '{}'},
+				{text: null},
+				{text: 'null'},
+				{text: undefined},
+				{text: 'undefined'},
 			];
 			var result = docPreprocessor.preprocessNode(ddContent);
 
@@ -138,13 +137,13 @@ describe('DocPreprocessor', function () {
 		it('should replace tab as 4 spaces', function () {
 			var ddContent = [
 				'a\tb',
-				{ text: 'a\tb' },
+				{text: 'a\tb'},
 				'a\tb\tc',
-				{ text: 'a\tb\tc' },
+				{text: 'a\tb\tc'},
 				{
 					text: [
 						'A\tB',
-						{ text: 'A\tB' },
+						{text: 'A\tB'},
 					]
 				}
 			];
@@ -188,8 +187,7 @@ describe('DocPreprocessor', function () {
 		it('should support simple toc on begin of document', function () {
 			var ddContent = [
 				{
-					toc: {
-					}
+					toc: {}
 				},
 				{
 					text: 'Header 1',
@@ -222,8 +220,7 @@ describe('DocPreprocessor', function () {
 					tocItem: true
 				},
 				{
-					toc: {
-					}
+					toc: {}
 				},
 			];
 			var result = docPreprocessor.preprocessDocument(ddContent);
@@ -239,4 +236,54 @@ describe('DocPreprocessor', function () {
 
 	});
 
+	describe('section', function () {
+
+		it('should support section', function () {
+			var ddContent = [
+				{
+					section: [],
+				},
+				{
+					section: [],
+				},
+			];
+			assert.doesNotThrow(function () {
+				docPreprocessor.preprocessDocument(ddContent);
+			});
+		});
+
+		it('should support section in stack', function () {
+			var ddContent = [
+				{
+					stack: [
+						{
+							section: [],
+						},
+						{
+							section: [],
+						},
+					]
+				}
+			];
+			assert.doesNotThrow(function () {
+				docPreprocessor.preprocessDocument(ddContent);
+			});
+		});
+
+		it('should support section only in root', function () {
+			var ddContent = [
+				{
+					table: {
+						body: [
+							[{section: []}],
+						]
+					}
+				},
+			];
+
+			assert.throws(() => docPreprocessor.preprocessDocument(ddContent), /Incorrect document structure, section node is only allowed at the root level of document structure/);
+		});
+
+	});
+
 });