Removed the 'model.Node#document.' property.

src/model/node.js

@@ -188,23 +188,6 @@ export default class Node {
 		return root;
 	}
 
-	/**
-	 * {@link module:engine/model/document~Document Document} that owns this node or `null` if the node has no parent or is inside
-	 * a {@link module:engine/model/documentfragment~DocumentFragment DocumentFragment}.
-	 *
-	 * @readonly
-	 * @type {module:engine/model/document~Document|null}
-	 */
-	get document() {
-		// This is a top element of a sub-tree.
-		if ( this.root == this ) {
-			return null;
-		}
-
-		// Root may be `DocumentFragment` which does not have document property.
-		return this.root.document || null;
-	}
-
 	/**
 	 * Gets path to the node. The path is an array containing starting offsets of consecutive ancestors of this node,
 	 * beginning from {@link module:engine/model/node~Node#root root}, down to this node's starting offset. The path can be used to

src/model/selection.js

@@ -829,7 +829,9 @@ function isUnvisitedBlock( element, visited ) {
 
 	visited.add( element );
 
-	return element.document.model.schema.isBlock( element ) && element.parent;
+	const document = element.is( 'rootElement' ) ? element.document : element.root.document;
+
+	return document.model.schema.isBlock( element ) && element.parent;
 }
 
 // Checks if the given element is a $block was not previously visited and is a top block in a range.
@@ -841,7 +843,9 @@ function isUnvisitedTopBlock( element, visited, range ) {
 // It will search until first ancestor that is a limit element.
 // Marks all ancestors as already visited to not include any of them later on.
 function getParentBlock( position, visited ) {
-	const schema = position.parent.document.model.schema;
+	const element = position.parent;
+	const document = element.is( 'rootElement' ) ? element.document : element.root.document;
+	const schema = document.model.schema;
 
 	const ancestors = position.parent.getAncestors( { parentFirst: true, includeSelf: true } );
 
@@ -887,7 +891,8 @@ function isTopBlockInRange( block, range ) {
 // @param {module:engine/model/node~Node} node
 // @returns {module:engine/model/node~Node|undefined}
 function findAncestorBlock( node ) {
-	const schema = node.document.model.schema;
+	const document = node.is( 'rootElement' ) ? node.document : node.root.document;
+	const schema = document.model.schema;
 
 	let parent = node.parent;
 

src/model/textproxy.js

@@ -163,17 +163,6 @@ export default class TextProxy {
 		return this.textNode.root;
 	}
 
-	/**
-	 * {@link module:engine/model/document~Document Document} that owns text node represented by this text proxy or `null` if the text node
-	 * has no parent or is inside a {@link module:engine/model/documentfragment~DocumentFragment DocumentFragment}.
-	 *
-	 * @readonly
-	 * @type {module:engine/model/document~Document|null}
-	 */
-	get document() {
-		return this.textNode.document;
-	}
-
 	/**
 	 * Checks whether this object is of the given.
 	 *

tests/model/node.js

@@ -75,25 +75,6 @@ describe( 'Node', () => {
 
 			expect( node ).to.have.property( 'previousSibling' ).that.is.null;
 		} );
-
-		it( 'document', () => {
-			expect( root ).to.have.property( 'document' ).that.equals( doc );
-
-			expect( one ).to.have.property( 'document' ).that.equals( doc );
-			expect( two ).to.have.property( 'document' ).that.equals( doc );
-			expect( three ).to.have.property( 'document' ).that.equals( doc );
-
-			expect( textBA ).to.have.property( 'document' ).that.equals( doc );
-			expect( img ).to.have.property( 'document' ).that.equals( doc );
-			expect( textR ).to.have.property( 'document' ).that.equals( doc );
-
-			expect( node ).to.have.property( 'document' ).that.is.null;
-
-			// DocumentFragment does not have document property, so node's document property should be null.
-			const docFrag = new DocumentFragment();
-			docFrag._appendChild( node );
-			expect( node ).to.have.property( 'document' ).that.is.null;
-		} );
 	} );
 
 	describe( 'constructor()', () => {

tests/model/textproxy.js

@@ -38,11 +38,6 @@ describe( 'TextProxy', () => {
 		expect( textProxyNoParent ).to.have.property( 'root' ).that.equals( textNoParent );
 	} );
 
-	it( 'should have document property', () => {
-		expect( textProxy ).to.have.property( 'document' ).that.equals( doc );
-		expect( textProxyNoParent ).to.have.property( 'document' ).that.equals( null );
-	} );
-
 	it( 'should have parent property', () => {
 		expect( textProxy ).to.have.property( 'parent' ).that.equals( element );
 		expect( textProxyNoParent ).to.have.property( 'parent' ).that.equals( null );