From 555b22a6eec54431396487b54cc0b5750d4851f0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20Go=C5=82aszewski?= <jodator@jodator.net>
Date: Fri, 3 Apr 2020 14:15:46 +0200
Subject: [PATCH 01/11] Fix wrong assertions in remove column command tests.

---
 .../tests/commands/removecolumncommand.js     | 35 +++++++++++++------
 1 file changed, 25 insertions(+), 10 deletions(-)

diff --git a/packages/ckeditor5-table/tests/commands/removecolumncommand.js b/packages/ckeditor5-table/tests/commands/removecolumncommand.js
index ad76d108292..08e5f677c6c 100644
--- a/packages/ckeditor5-table/tests/commands/removecolumncommand.js
+++ b/packages/ckeditor5-table/tests/commands/removecolumncommand.js
@@ -418,7 +418,7 @@ describe( 'RemoveColumnCommand', () => {
 			] ) );
 		} );
 
-		it( 'should work property if the rowspan is in the first column (#1)', () => {
+		it( 'should work property if the rowspan is in the first column (the other cell in row is selected)', () => {
 			setData( model, modelTable( [
 				[ { rowspan: 2, contents: '00' }, '[]01' ],
 				[ '10' ]
@@ -427,11 +427,11 @@ describe( 'RemoveColumnCommand', () => {
 			command.execute();
 
 			assertEqualMarkup( getData( model ), modelTable( [
-				[ { rowspan: 2, contents: '[]00' } ]
+				[ '[]00' ]
 			] ) );
 		} );
 
-		it( 'should work property if the rowspan is in the first column (#2)', () => {
+		it( 'should work property if the rowspan is in the first column (the cell in row below is selected)', () => {
 			setData( model, modelTable( [
 				[ { rowspan: 2, contents: '00' }, '01' ],
 				[ '[]10' ]
@@ -440,11 +440,11 @@ describe( 'RemoveColumnCommand', () => {
 			command.execute();
 
 			assertEqualMarkup( getData( model ), modelTable( [
-				[ { rowspan: 2, contents: '[]00' } ]
+				[ '[]00' ]
 			] ) );
 		} );
 
-		it( 'should work property if the rowspan is in the first column (#3)', () => {
+		it( 'should work property if the rowspan is in the first column (the cell with rowspan is selected)', () => {
 			setData( model, modelTable( [
 				[ { rowspan: 2, contents: '00[]' }, '01' ],
 				[ '10' ]
@@ -458,7 +458,7 @@ describe( 'RemoveColumnCommand', () => {
 			] ) );
 		} );
 
-		it( 'should work property if the rowspan is in the last column (#1)', () => {
+		it( 'should work property if the rowspan is in the last column (the other cell in row is selected)', () => {
 			setData( model, modelTable( [
 				[ '[]00', { rowspan: 2, contents: '01' } ],
 				[ '10' ]
@@ -467,11 +467,11 @@ describe( 'RemoveColumnCommand', () => {
 			command.execute();
 
 			assertEqualMarkup( getData( model ), modelTable( [
-				[ { rowspan: 2, contents: '[]01' } ]
+				[ '[]01' ]
 			] ) );
 		} );
 
-		it( 'should work property if the rowspan is in the last column (#2)', () => {
+		it( 'should work property if the rowspan is in the last column (the cell in row below is selected)', () => {
 			setData( model, modelTable( [
 				[ '00', { rowspan: 2, contents: '01' } ],
 				[ '[]10' ]
@@ -480,11 +480,11 @@ describe( 'RemoveColumnCommand', () => {
 			command.execute();
 
 			assertEqualMarkup( getData( model ), modelTable( [
-				[ { rowspan: 2, contents: '[]01' } ]
+				[ '[]01' ]
 			] ) );
 		} );
 
-		it( 'should work property if the rowspan is in the last column (#3)', () => {
+		it( 'should work property if the rowspan is in the last column (the cell with rowspan is selected)', () => {
 			setData( model, modelTable( [
 				[ '00', { rowspan: 2, contents: '[]01' } ],
 				[ '10' ]
@@ -497,5 +497,20 @@ describe( 'RemoveColumnCommand', () => {
 				[ '10' ]
 			] ) );
 		} );
+
+		it( 'should remove column if removing row with one column - other columns are spanned', () => {
+			setData( model, modelTable( [
+				[ '[]00', { rowspan: 2, contents: '01' }, { rowspan: 2, contents: '02' } ],
+				[ '10' ],
+				[ '20', '21', '22' ]
+			] ) );
+
+			command.execute();
+
+			assertEqualMarkup( getData( model ), modelTable( [
+				[ '[]01', '02' ],
+				[ '21', '22' ]
+			] ) );
+		} );
 	} );
 } );

From d7542b03765d5f777829e2a9f8bf43b67d028147 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20Go=C5=82aszewski?= <jodator@jodator.net>
Date: Fri, 3 Apr 2020 14:25:48 +0200
Subject: [PATCH 02/11] Use removeRow() method from TableUtils.

---
 .../ckeditor5-table/src/commands/removecolumncommand.js     | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/packages/ckeditor5-table/src/commands/removecolumncommand.js b/packages/ckeditor5-table/src/commands/removecolumncommand.js
index d21aa7a3cdf..1494284f4e0 100644
--- a/packages/ckeditor5-table/src/commands/removecolumncommand.js
+++ b/packages/ckeditor5-table/src/commands/removecolumncommand.js
@@ -92,7 +92,9 @@ export default class RemoveColumnCommand extends Command {
 	 * @param {module:engine/model/writer~Writer} writer
 	 */
 	_removeColumn( removedColumnIndex, table, writer ) {
-		for ( const { cell, column, colspan } of new TableWalker( table ) ) {
+		const tableUtils = this.editor.plugins.get( 'TableUtils' );
+
+		for ( const { cell, column, colspan } of [ ...new TableWalker( table ) ] ) {
 			// If colspaned cell overlaps removed column decrease its span.
 			if ( column <= removedColumnIndex && colspan > 1 && column + colspan > removedColumnIndex ) {
 				updateNumericAttribute( 'colspan', colspan - 1, cell, writer );
@@ -105,7 +107,7 @@ export default class RemoveColumnCommand extends Command {
 				// If the cell was the last one in the row, get rid of the entire row.
 				// https://github.com/ckeditor/ckeditor5/issues/6429
 				if ( !cellRow.childCount ) {
-					writer.remove( cellRow );
+					tableUtils.removeRow( cellRow.index, table, writer );
 				}
 			}
 		}

From 3cbaaa312c82746b20eb3b34ca7b2cd722a974b8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20Go=C5=82aszewski?= <jodator@jodator.net>
Date: Tue, 7 Apr 2020 10:27:48 +0200
Subject: [PATCH 03/11] Add test cases for TableUtils#removeColumn().

---
 packages/ckeditor5-table/tests/tableutils.js | 191 +++++++++++++++++++
 1 file changed, 191 insertions(+)

diff --git a/packages/ckeditor5-table/tests/tableutils.js b/packages/ckeditor5-table/tests/tableutils.js
index 8412907bc02..5cd8a7d1c88 100644
--- a/packages/ckeditor5-table/tests/tableutils.js
+++ b/packages/ckeditor5-table/tests/tableutils.js
@@ -960,4 +960,195 @@ describe( 'TableUtils', () => {
 			} );
 		} );
 	} );
+
+	describe( 'removeColumn()', () => {
+		describe( 'single row', () => {
+			it( 'should remove a given column', () => {
+				setData( model, modelTable( [
+					[ '00', '01', '02' ],
+					[ '10', '11', '12' ],
+					[ '20', '21', '22' ]
+				] ) );
+
+				tableUtils.removeColumn( { at: 1 } );
+
+				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
+					[ '00', '02' ],
+					[ '10', '12' ],
+					[ '20', '22' ]
+				] ) );
+			} );
+
+			it( 'should remove a given column from a table start', () => {
+				setData( model, modelTable( [
+					[ '00', '01' ],
+					[ '10', '11' ],
+					[ '20', '21' ]
+				] ) );
+
+				tableUtils.removeColumn( { at: 0 } );
+
+				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
+					[ '01' ],
+					[ '11' ],
+					[ '21' ]
+				] ) );
+			} );
+
+			it( 'should change heading columns if removing a heading column', () => {
+				setData( model, modelTable( [
+					[ '00', '01' ],
+					[ '10', '11' ],
+					[ '20', '21' ]
+				], { headingColumns: 2 } ) );
+
+				tableUtils.removeColumn( { at: 0 } );
+
+				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
+					[ '01' ],
+					[ '11' ],
+					[ '21' ]
+				], { headingColumns: 1 } ) );
+			} );
+
+			it( 'should decrease colspan of table cells from previous column', () => {
+				setData( model, modelTable( [
+					[ { colspan: 4, contents: '00' }, '03' ],
+					[ { colspan: 3, contents: '10' }, '13' ],
+					[ { colspan: 2, contents: '20' }, '22', '23' ],
+					[ '30', { colspan: 2, contents: '31' }, '33' ],
+					[ '40', '41', '42', '43' ]
+				] ) );
+
+				tableUtils.removeColumn( { at: 2 } );
+
+				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
+					[ { colspan: 3, contents: '00' }, '03' ],
+					[ { colspan: 2, contents: '10' }, '13' ],
+					[ { colspan: 2, contents: '20' }, '23' ],
+					[ '30', '31', '33' ],
+					[ '40', '41', '43' ]
+
+				] ) );
+			} );
+
+			it( 'should decrease colspan of cells that are on removed column', () => {
+				setData( model, modelTable( [
+					[ { colspan: 3, contents: '00' }, '03' ],
+					[ { colspan: 2, contents: '10' }, '13' ],
+					[ '20', '21', '22', '23' ]
+				] ) );
+
+				tableUtils.removeColumn( { at: 0 } );
+
+				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
+					[ { colspan: 2, contents: '00' }, '03' ],
+					[ '10', '13' ],
+					[ '21', '22', '23' ]
+				] ) );
+			} );
+
+			it( 'should move focus to previous column of removed cell if in last column', () => {
+				setData( model, modelTable( [
+					[ '00', '01', '02' ],
+					[ '10', '11', '12' ],
+					[ '20', '21', '22' ]
+				] ) );
+
+				tableUtils.removeColumn( { at: 2 } );
+
+				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
+					[ '00', '01' ],
+					[ '10', '11' ],
+					[ '20', '21' ]
+				] ) );
+			} );
+		} );
+
+		describe( 'multiple columns', () => {
+			it( 'should properly remove two first columns', () => {
+				setData( model, modelTable( [
+					[ '00', '01', '02' ],
+					[ '10', '11', '12' ],
+					[ '20', '21', '22' ],
+					[ '30', '31', '32' ]
+				] ) );
+
+				tableUtils.removeColumn( { at: 0, columns: 2 } );
+
+				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
+					[ '02' ],
+					[ '12' ],
+					[ '22' ],
+					[ '32' ]
+				] ) );
+			} );
+
+			it( 'should properly remove two middle columns', () => {
+				setData( model, modelTable( [
+					[ '00', '01', '02', '03' ],
+					[ '10', '11', '12', '13' ],
+					[ '20', '21', '22', '23' ],
+					[ '30', '31', '32', '33' ]
+				] ) );
+
+				tableUtils.removeColumn( { at: 1, columns: 2 } );
+
+				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
+					[ '00', '03' ],
+					[ '10', '13' ],
+					[ '20', '23' ],
+					[ '30', '33' ]
+				] ) );
+			} );
+
+			it( 'should properly remove two last columns', () => {
+				setData( model, modelTable( [
+					[ '00', '01', '02' ],
+					[ '10', '11', '12' ],
+					[ '20', '21', '22' ],
+					[ '30', '31', '32' ]
+				] ) );
+
+				tableUtils.removeColumn( { at: 1, columns: 2 } );
+
+				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
+					[ '00' ],
+					[ '10' ],
+					[ '20' ],
+					[ '30' ]
+				] ) );
+			} );
+
+			it( 'should properly remove multiple heading columns', () => {
+				setData( model, modelTable( [
+					[ '00', '01', '02', '03', '04' ],
+					[ '10', '11', '12', '13', '14' ]
+				], { headingColumns: 3 } ) );
+
+				tableUtils.removeColumn( { at: 1, columns: 3 } );
+
+				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
+					[ '00', '04' ],
+					[ '10', '14' ]
+				], { headingColumns: 1 } ) );
+			} );
+
+			it( 'should properly calculate truncated colspans', () => {
+				setData( model, modelTable( [
+					[ { contents: '00', colspan: 3 } ],
+					[ '10', '11', '12' ],
+					[ '20', '21', '22' ]
+				] ) );
+
+				tableUtils.removeColumn( { at: 0, columns: 2 } );
+
+				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
+					[ '00' ],
+					[ '12' ],
+					[ '22' ]
+				] ) );
+			} );
+		} );
+	} );
 } );

From 97bc2cb9ebd35d2be965989ade10a6c839082787 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20Go=C5=82aszewski?= <jodator@jodator.net>
Date: Tue, 7 Apr 2020 11:58:59 +0200
Subject: [PATCH 04/11] Update remove column test cases.

---
 packages/ckeditor5-table/tests/tableutils.js | 89 ++++++++++++++++----
 1 file changed, 71 insertions(+), 18 deletions(-)

diff --git a/packages/ckeditor5-table/tests/tableutils.js b/packages/ckeditor5-table/tests/tableutils.js
index 5cd8a7d1c88..9ea9400f3ea 100644
--- a/packages/ckeditor5-table/tests/tableutils.js
+++ b/packages/ckeditor5-table/tests/tableutils.js
@@ -961,7 +961,7 @@ describe( 'TableUtils', () => {
 		} );
 	} );
 
-	describe( 'removeColumn()', () => {
+	describe( 'removeColumns()', () => {
 		describe( 'single row', () => {
 			it( 'should remove a given column', () => {
 				setData( model, modelTable( [
@@ -970,7 +970,7 @@ describe( 'TableUtils', () => {
 					[ '20', '21', '22' ]
 				] ) );
 
-				tableUtils.removeColumn( { at: 1 } );
+				tableUtils.removeColumns( root.getNodeByPath( [ 0 ] ), { at: 1 } );
 
 				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
 					[ '00', '02' ],
@@ -986,7 +986,7 @@ describe( 'TableUtils', () => {
 					[ '20', '21' ]
 				] ) );
 
-				tableUtils.removeColumn( { at: 0 } );
+				tableUtils.removeColumns( root.getNodeByPath( [ 0 ] ), { at: 0 } );
 
 				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
 					[ '01' ],
@@ -1002,7 +1002,7 @@ describe( 'TableUtils', () => {
 					[ '20', '21' ]
 				], { headingColumns: 2 } ) );
 
-				tableUtils.removeColumn( { at: 0 } );
+				tableUtils.removeColumns( root.getNodeByPath( [ 0 ] ), { at: 0 } );
 
 				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
 					[ '01' ],
@@ -1020,7 +1020,7 @@ describe( 'TableUtils', () => {
 					[ '40', '41', '42', '43' ]
 				] ) );
 
-				tableUtils.removeColumn( { at: 2 } );
+				tableUtils.removeColumns( root.getNodeByPath( [ 0 ] ), { at: 2 } );
 
 				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
 					[ { colspan: 3, contents: '00' }, '03' ],
@@ -1039,7 +1039,7 @@ describe( 'TableUtils', () => {
 					[ '20', '21', '22', '23' ]
 				] ) );
 
-				tableUtils.removeColumn( { at: 0 } );
+				tableUtils.removeColumns( root.getNodeByPath( [ 0 ] ), { at: 0 } );
 
 				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
 					[ { colspan: 2, contents: '00' }, '03' ],
@@ -1048,19 +1048,72 @@ describe( 'TableUtils', () => {
 				] ) );
 			} );
 
-			it( 'should move focus to previous column of removed cell if in last column', () => {
+			it( 'should remove column with rowspan (first column)', () => {
 				setData( model, modelTable( [
-					[ '00', '01', '02' ],
-					[ '10', '11', '12' ],
+					[ { rowspan: 2, contents: '00' }, '01' ],
+					[ '10' ]
+				] ) );
+
+				tableUtils.removeColumns( root.getNodeByPath( [ 0 ] ), { at: 0 } );
+
+				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
+					[ '01' ],
+					[ '10' ]
+				] ) );
+			} );
+
+			it( 'should remove column with rowspan (last column)', () => {
+				setData( model, modelTable( [
+					[ '00', { rowspan: 2, contents: '01' } ],
+					[ '10' ]
+				] ) );
+
+				tableUtils.removeColumns( root.getNodeByPath( [ 0 ] ), { at: 1 } );
+
+				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
+					[ '00' ],
+					[ '10' ]
+				] ) );
+			} );
+
+			it( 'should remove column if other column is rowspanned (last column)', () => {
+				setData( model, modelTable( [
+					[ '00', { rowspan: 2, contents: '01' } ],
+					[ '10' ]
+				] ) );
+
+				tableUtils.removeColumns( root.getNodeByPath( [ 0 ] ), { at: 0 } );
+
+				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
+					[ '01' ]
+				] ) );
+			} );
+
+			it( 'should remove column if other column is rowspanned (first column)', () => {
+				setData( model, modelTable( [
+					[ { rowspan: 2, contents: '00' }, '01' ],
+					[ '11' ]
+				] ) );
+
+				tableUtils.removeColumns( root.getNodeByPath( [ 0 ] ), { at: 1 } );
+
+				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
+					[ '00' ]
+				] ) );
+			} );
+
+			it( 'should remove column if removing row with one column - other columns are spanned', () => {
+				setData( model, modelTable( [
+					[ '00', { rowspan: 2, contents: '01' }, { rowspan: 2, contents: '02' } ],
+					[ '10' ],
 					[ '20', '21', '22' ]
 				] ) );
 
-				tableUtils.removeColumn( { at: 2 } );
+				tableUtils.removeColumns( root.getNodeByPath( [ 0 ] ), { at: 0 } );
 
 				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
-					[ '00', '01' ],
-					[ '10', '11' ],
-					[ '20', '21' ]
+					[ '01', '02' ],
+					[ '21', '22' ]
 				] ) );
 			} );
 		} );
@@ -1074,7 +1127,7 @@ describe( 'TableUtils', () => {
 					[ '30', '31', '32' ]
 				] ) );
 
-				tableUtils.removeColumn( { at: 0, columns: 2 } );
+				tableUtils.removeColumns( root.getNodeByPath( [ 0 ] ), { at: 0, columns: 2 } );
 
 				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
 					[ '02' ],
@@ -1092,7 +1145,7 @@ describe( 'TableUtils', () => {
 					[ '30', '31', '32', '33' ]
 				] ) );
 
-				tableUtils.removeColumn( { at: 1, columns: 2 } );
+				tableUtils.removeColumns( root.getNodeByPath( [ 0 ] ), { at: 1, columns: 2 } );
 
 				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
 					[ '00', '03' ],
@@ -1110,7 +1163,7 @@ describe( 'TableUtils', () => {
 					[ '30', '31', '32' ]
 				] ) );
 
-				tableUtils.removeColumn( { at: 1, columns: 2 } );
+				tableUtils.removeColumns( root.getNodeByPath( [ 0 ] ), { at: 1, columns: 2 } );
 
 				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
 					[ '00' ],
@@ -1126,7 +1179,7 @@ describe( 'TableUtils', () => {
 					[ '10', '11', '12', '13', '14' ]
 				], { headingColumns: 3 } ) );
 
-				tableUtils.removeColumn( { at: 1, columns: 3 } );
+				tableUtils.removeColumns( root.getNodeByPath( [ 0 ] ), { at: 1, columns: 3 } );
 
 				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
 					[ '00', '04' ],
@@ -1141,7 +1194,7 @@ describe( 'TableUtils', () => {
 					[ '20', '21', '22' ]
 				] ) );
 
-				tableUtils.removeColumn( { at: 0, columns: 2 } );
+				tableUtils.removeColumns( root.getNodeByPath( [ 0 ] ), { at: 0, columns: 2 } );
 
 				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
 					[ '00' ],

From f7c92f39b3548163acd36c64d371e9b39eeb0cd2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20Go=C5=82aszewski?= <jodator@jodator.net>
Date: Tue, 7 Apr 2020 11:59:28 +0200
Subject: [PATCH 05/11] Move column removing logic to TableUtils#removeColumns.

---
 .../src/commands/removecolumncommand.js       | 56 ++-----------------
 packages/ckeditor5-table/src/tableutils.js    | 43 ++++++++++++++
 2 files changed, 47 insertions(+), 52 deletions(-)

diff --git a/packages/ckeditor5-table/src/commands/removecolumncommand.js b/packages/ckeditor5-table/src/commands/removecolumncommand.js
index 1494284f4e0..5523a52cfe7 100644
--- a/packages/ckeditor5-table/src/commands/removecolumncommand.js
+++ b/packages/ckeditor5-table/src/commands/removecolumncommand.js
@@ -10,7 +10,6 @@
 import Command from '@ckeditor/ckeditor5-core/src/command';
 
 import TableWalker from '../tablewalker';
-import { updateNumericAttribute } from './utils';
 import { getSelectionAffectedTableCells } from '../utils';
 
 /**
@@ -69,61 +68,14 @@ export default class RemoveColumnCommand extends Command {
 			// A temporary workaround to avoid the "model-selection-range-intersects" error.
 			writer.setSelection( writer.createRangeOn( table ) );
 
-			adjustHeadingColumns( table, removedColumnIndexes, writer );
-
-			for (
-				let removedColumnIndex = removedColumnIndexes.last;
-				removedColumnIndex >= removedColumnIndexes.first;
-				removedColumnIndex--
-			) {
-				this._removeColumn( removedColumnIndex, table, writer );
-			}
+			this.editor.plugins.get( 'TableUtils' ).removeColumns( {
+				at: removedColumnIndexes.first,
+				columns: removedColumnIndexes.last - removedColumnIndexes.first
+			} );
 
 			writer.setSelection( writer.createPositionAt( cellToFocus, 0 ) );
 		} );
 	}
-
-	/**
-	 * Removes a column from the given `table`.
-	 *
-	 * @private
-	 * @param {Number} removedColumnIndex Index of the column that should be removed.
-	 * @param {module:engine/model/element~Element} table
-	 * @param {module:engine/model/writer~Writer} writer
-	 */
-	_removeColumn( removedColumnIndex, table, writer ) {
-		const tableUtils = this.editor.plugins.get( 'TableUtils' );
-
-		for ( const { cell, column, colspan } of [ ...new TableWalker( table ) ] ) {
-			// If colspaned cell overlaps removed column decrease its span.
-			if ( column <= removedColumnIndex && colspan > 1 && column + colspan > removedColumnIndex ) {
-				updateNumericAttribute( 'colspan', colspan - 1, cell, writer );
-			} else if ( column === removedColumnIndex ) {
-				const cellRow = cell.parent;
-
-				// The cell in removed column has colspan of 1.
-				writer.remove( cell );
-
-				// If the cell was the last one in the row, get rid of the entire row.
-				// https://github.com/ckeditor/ckeditor5/issues/6429
-				if ( !cellRow.childCount ) {
-					tableUtils.removeRow( cellRow.index, table, writer );
-				}
-			}
-		}
-	}
-}
-
-// Updates heading columns attribute if removing a row from head section.
-function adjustHeadingColumns( table, removedColumnIndexes, writer ) {
-	const headingColumns = table.getAttribute( 'headingColumns' ) || 0;
-
-	if ( headingColumns && removedColumnIndexes.first <= headingColumns ) {
-		const headingsRemoved = Math.min( headingColumns - 1 /* Other numbers are 0-based */, removedColumnIndexes.last ) -
-			removedColumnIndexes.first + 1;
-
-		writer.setAttribute( 'headingColumns', headingColumns - headingsRemoved, table );
-	}
 }
 
 // Returns a proper table cell to focus after removing a column.
diff --git a/packages/ckeditor5-table/src/tableutils.js b/packages/ckeditor5-table/src/tableutils.js
index 69bd7a2267d..f4bf3a81b35 100644
--- a/packages/ckeditor5-table/src/tableutils.js
+++ b/packages/ckeditor5-table/src/tableutils.js
@@ -307,6 +307,37 @@ export default class TableUtils extends Plugin {
 		} );
 	}
 
+	removeColumns( table, options ) {
+		const model = this.editor.model;
+		const first = options.at;
+		const columnsToRemove = options.columns || 1;
+		const last = options.at + columnsToRemove - 1;
+
+		model.change( writer => {
+			adjustHeadingColumns( table, { first, last }, writer );
+
+			for ( let removedColumnIndex = last; removedColumnIndex >= first; removedColumnIndex-- ) {
+				for ( const { cell, column, colspan } of [ ...new TableWalker( table ) ] ) {
+					// If colspaned cell overlaps removed column decrease its span.
+					if ( column <= removedColumnIndex && colspan > 1 && column + colspan > removedColumnIndex ) {
+						updateNumericAttribute( 'colspan', colspan - 1, cell, writer );
+					} else if ( column === removedColumnIndex ) {
+						const cellRow = cell.parent;
+
+						// The cell in removed column has colspan of 1.
+						writer.remove( cell );
+
+						// If the cell was the last one in the row, get rid of the entire row.
+						// https://github.com/ckeditor/ckeditor5/issues/6429
+						if ( !cellRow.childCount ) {
+							this.removeRows( table, { at: cellRow.index } );
+						}
+					}
+				}
+			}
+		} );
+	}
+
 	/**
 	 * Divides a table cell vertically into several ones.
 	 *
@@ -715,3 +746,15 @@ function getNewHeadingRowsValue( first, last, headingRows ) {
 
 	return first;
 }
+
+// Updates heading columns attribute if removing a row from head section.
+function adjustHeadingColumns( table, removedColumnIndexes, writer ) {
+	const headingColumns = table.getAttribute( 'headingColumns' ) || 0;
+
+	if ( headingColumns && removedColumnIndexes.first <= headingColumns ) {
+		const headingsRemoved = Math.min( headingColumns - 1 /* Other numbers are 0-based */, removedColumnIndexes.last ) -
+			removedColumnIndexes.first + 1;
+
+		writer.setAttribute( 'headingColumns', headingColumns - headingsRemoved, table );
+	}
+}

From 686afd7d3dce7762bff060db9794eeacd6648995 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20Go=C5=82aszewski?= <jodator@jodator.net>
Date: Tue, 7 Apr 2020 12:15:53 +0200
Subject: [PATCH 06/11] Pass proper parameters to TableUtils.removeColumns()
 ins RemoveColumnCommand.

---
 .../ckeditor5-table/src/commands/removecolumncommand.js     | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/packages/ckeditor5-table/src/commands/removecolumncommand.js b/packages/ckeditor5-table/src/commands/removecolumncommand.js
index 5523a52cfe7..0e159ed5167 100644
--- a/packages/ckeditor5-table/src/commands/removecolumncommand.js
+++ b/packages/ckeditor5-table/src/commands/removecolumncommand.js
@@ -68,9 +68,11 @@ export default class RemoveColumnCommand extends Command {
 			// A temporary workaround to avoid the "model-selection-range-intersects" error.
 			writer.setSelection( writer.createRangeOn( table ) );
 
-			this.editor.plugins.get( 'TableUtils' ).removeColumns( {
+			const columnsToRemove = removedColumnIndexes.last - removedColumnIndexes.first + 1;
+
+			this.editor.plugins.get( 'TableUtils' ).removeColumns( table, {
 				at: removedColumnIndexes.first,
-				columns: removedColumnIndexes.last - removedColumnIndexes.first
+				columns: columnsToRemove
 			} );
 
 			writer.setSelection( writer.createPositionAt( cellToFocus, 0 ) );

From 2636b225ffc618d3322d765d1018be057786defe Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20Go=C5=82aszewski?= <jodator@jodator.net>
Date: Tue, 7 Apr 2020 13:27:34 +0200
Subject: [PATCH 07/11] Add docs for TableUtils.removeColumns() method.

---
 packages/ckeditor5-table/src/tableutils.js | 29 ++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/packages/ckeditor5-table/src/tableutils.js b/packages/ckeditor5-table/src/tableutils.js
index f4bf3a81b35..46ff1de3144 100644
--- a/packages/ckeditor5-table/src/tableutils.js
+++ b/packages/ckeditor5-table/src/tableutils.js
@@ -307,6 +307,35 @@ export default class TableUtils extends Plugin {
 		} );
 	}
 
+	/**
+	 * Removes columns from the given `table`.
+	 *
+	 * This method re-calculates the table geometry including `colspan` attribute of table cells overlapping removed columns
+	 * and table headings values.
+	 *
+	 *		editor.plugins.get( 'TableUtils' ).removeColumns( table, { at: 1, columns: 2 } );
+	 *
+	 * Executing the above code in the context of the table on the left will transform its structure as presented on the right:
+	 *
+	 *		  0   1   2   3   4                       0   1   2
+	 *		┌───────────────┬───┐                   ┌───────┬───┐
+	 *		│ a             │ b │                   │ a     │ b │
+	 *		│               ├───┤                   │       ├───┤
+	 *		│               │ c │                   │       │ c │
+	 *		├───┬───┬───┬───┼───┤     will give:    ├───┬───┼───┤
+	 *		│ d │ e │ f │ g │ h │                   │ d │ g │ h │
+	 *		├───┼───┼───┤   ├───┤                   ├───┤   ├───┤
+	 *		│ i │ j │ k │   │ l │                   │ i │   │ l │
+	 *		├───┴───┴───┴───┴───┤                   ├───┴───┴───┤
+	 *		│ m                 │                   │ m         │
+	 *		└───────────────────┘                   └───────────┘
+	 *		      ^---- remove from here, `at` = 1, `columns` = 2
+	 *
+	 * @param {module:engine/model/element~Element} table
+	 * @param {Object} options
+	 * @param {Number} options.at The row index at which the removing columns will start.
+	 * @param {Number} [options.columns=1] The number of columns to remove.
+	 */
 	removeColumns( table, options ) {
 		const model = this.editor.model;
 		const first = options.at;

From e48d63df3867bbdf5a27a04e3ee6d32b58e0a599 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20Go=C5=82aszewski?= <jodator@jodator.net>
Date: Wed, 8 Apr 2020 12:08:22 +0200
Subject: [PATCH 08/11] Fix tables used in tests.

---
 .../tests/commands/removecolumncommand.js     | 32 +++++++++----------
 packages/ckeditor5-table/tests/tableutils.js  | 28 ++++++++--------
 2 files changed, 30 insertions(+), 30 deletions(-)

diff --git a/packages/ckeditor5-table/tests/commands/removecolumncommand.js b/packages/ckeditor5-table/tests/commands/removecolumncommand.js
index 08e5f677c6c..905727c963e 100644
--- a/packages/ckeditor5-table/tests/commands/removecolumncommand.js
+++ b/packages/ckeditor5-table/tests/commands/removecolumncommand.js
@@ -367,21 +367,21 @@ describe( 'RemoveColumnCommand', () => {
 
 		it( 'should decrease colspan of table cells from previous column', () => {
 			setData( model, modelTable( [
-				[ { colspan: 4, contents: '00' }, '03' ],
-				[ { colspan: 3, contents: '10' }, '13' ],
-				[ { colspan: 2, contents: '20' }, '22[]', '23' ],
-				[ '30', { colspan: 2, contents: '31' }, '33' ],
-				[ '40', '41', '42', '43' ]
+				[ { colspan: 4, contents: '00' }, '04' ],
+				[ { colspan: 3, contents: '10' }, '14' ],
+				[ { colspan: 2, contents: '20' }, '22[]', '23', '24' ],
+				[ '30', { colspan: 2, contents: '31' }, '33', '34' ],
+				[ '40', '41', '42', '43', '44' ]
 			] ) );
 
 			command.execute();
 
 			assertEqualMarkup( getData( model ), modelTable( [
-				[ { colspan: 3, contents: '00' }, '03' ],
-				[ { colspan: 2, contents: '10' }, '13' ],
-				[ { colspan: 2, contents: '20' }, '[]23' ],
-				[ '30', '31', '33' ],
-				[ '40', '41', '43' ]
+				[ { colspan: 3, contents: '00' }, '04' ],
+				[ { colspan: 2, contents: '10' }, '14' ],
+				[ { colspan: 2, contents: '20' }, '[]23', '24' ],
+				[ '30', '31', '33', '34' ],
+				[ '40', '41', '43', '44' ]
 
 			] ) );
 		} );
@@ -389,7 +389,7 @@ describe( 'RemoveColumnCommand', () => {
 		it( 'should decrease colspan of cells that are on removed column', () => {
 			setData( model, modelTable( [
 				[ { colspan: 3, contents: '[]00' }, '03' ],
-				[ { colspan: 2, contents: '10' }, '13' ],
+				[ { colspan: 2, contents: '10' }, '12', '13' ],
 				[ '20', '21', '22', '23' ]
 			] ) );
 
@@ -397,7 +397,7 @@ describe( 'RemoveColumnCommand', () => {
 
 			assertEqualMarkup( getData( model ), modelTable( [
 				[ { colspan: 2, contents: '[]00' }, '03' ],
-				[ '10', '13' ],
+				[ '10', '12', '13' ],
 				[ '21', '22', '23' ]
 			] ) );
 		} );
@@ -421,7 +421,7 @@ describe( 'RemoveColumnCommand', () => {
 		it( 'should work property if the rowspan is in the first column (the other cell in row is selected)', () => {
 			setData( model, modelTable( [
 				[ { rowspan: 2, contents: '00' }, '[]01' ],
-				[ '10' ]
+				[ '11' ]
 			] ) );
 
 			command.execute();
@@ -434,7 +434,7 @@ describe( 'RemoveColumnCommand', () => {
 		it( 'should work property if the rowspan is in the first column (the cell in row below is selected)', () => {
 			setData( model, modelTable( [
 				[ { rowspan: 2, contents: '00' }, '01' ],
-				[ '[]10' ]
+				[ '[]11' ]
 			] ) );
 
 			command.execute();
@@ -447,14 +447,14 @@ describe( 'RemoveColumnCommand', () => {
 		it( 'should work property if the rowspan is in the first column (the cell with rowspan is selected)', () => {
 			setData( model, modelTable( [
 				[ { rowspan: 2, contents: '00[]' }, '01' ],
-				[ '10' ]
+				[ '11' ]
 			] ) );
 
 			command.execute();
 
 			assertEqualMarkup( getData( model ), modelTable( [
 				[ '[]01' ],
-				[ '10' ]
+				[ '11' ]
 			] ) );
 		} );
 
diff --git a/packages/ckeditor5-table/tests/tableutils.js b/packages/ckeditor5-table/tests/tableutils.js
index facdc5e565f..b8930c8cc84 100644
--- a/packages/ckeditor5-table/tests/tableutils.js
+++ b/packages/ckeditor5-table/tests/tableutils.js
@@ -1013,21 +1013,21 @@ describe( 'TableUtils', () => {
 
 			it( 'should decrease colspan of table cells from previous column', () => {
 				setData( model, modelTable( [
-					[ { colspan: 4, contents: '00' }, '03' ],
-					[ { colspan: 3, contents: '10' }, '13' ],
-					[ { colspan: 2, contents: '20' }, '22', '23' ],
-					[ '30', { colspan: 2, contents: '31' }, '33' ],
-					[ '40', '41', '42', '43' ]
+					[ { colspan: 4, contents: '00' }, '04' ],
+					[ { colspan: 3, contents: '10' }, '14' ],
+					[ { colspan: 2, contents: '20' }, '22', '23', '24' ],
+					[ '30', { colspan: 2, contents: '31' }, '33', '34' ],
+					[ '40', '41', '42', '43', '44' ]
 				] ) );
 
 				tableUtils.removeColumns( root.getNodeByPath( [ 0 ] ), { at: 2 } );
 
 				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
-					[ { colspan: 3, contents: '00' }, '03' ],
-					[ { colspan: 2, contents: '10' }, '13' ],
-					[ { colspan: 2, contents: '20' }, '23' ],
-					[ '30', '31', '33' ],
-					[ '40', '41', '43' ]
+					[ { colspan: 3, contents: '00' }, '04' ],
+					[ { colspan: 2, contents: '10' }, '14' ],
+					[ { colspan: 2, contents: '20' }, '23', '24' ],
+					[ '30', '31', '33', '34' ],
+					[ '40', '41', '43', '44' ]
 
 				] ) );
 			} );
@@ -1035,7 +1035,7 @@ describe( 'TableUtils', () => {
 			it( 'should decrease colspan of cells that are on removed column', () => {
 				setData( model, modelTable( [
 					[ { colspan: 3, contents: '00' }, '03' ],
-					[ { colspan: 2, contents: '10' }, '13' ],
+					[ { colspan: 2, contents: '10' }, '12', '13' ],
 					[ '20', '21', '22', '23' ]
 				] ) );
 
@@ -1043,7 +1043,7 @@ describe( 'TableUtils', () => {
 
 				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
 					[ { colspan: 2, contents: '00' }, '03' ],
-					[ '10', '13' ],
+					[ '10', '12', '13' ],
 					[ '21', '22', '23' ]
 				] ) );
 			} );
@@ -1051,14 +1051,14 @@ describe( 'TableUtils', () => {
 			it( 'should remove column with rowspan (first column)', () => {
 				setData( model, modelTable( [
 					[ { rowspan: 2, contents: '00' }, '01' ],
-					[ '10' ]
+					[ '11' ]
 				] ) );
 
 				tableUtils.removeColumns( root.getNodeByPath( [ 0 ] ), { at: 0 } );
 
 				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
 					[ '01' ],
-					[ '10' ]
+					[ '11' ]
 				] ) );
 			} );
 

From 4822543193cd77361a09f5d51389e10a84289f87 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20Go=C5=82aszewski?= <jodator@jodator.net>
Date: Wed, 8 Apr 2020 12:11:04 +0200
Subject: [PATCH 09/11] Fix condition for updating heading columns in
 adjustHeadingColumns().

---
 packages/ckeditor5-table/src/tableutils.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/ckeditor5-table/src/tableutils.js b/packages/ckeditor5-table/src/tableutils.js
index b99984ba81a..f1a283276f3 100644
--- a/packages/ckeditor5-table/src/tableutils.js
+++ b/packages/ckeditor5-table/src/tableutils.js
@@ -780,7 +780,7 @@ function getNewHeadingRowsValue( first, last, headingRows ) {
 function adjustHeadingColumns( table, removedColumnIndexes, writer ) {
 	const headingColumns = table.getAttribute( 'headingColumns' ) || 0;
 
-	if ( headingColumns && removedColumnIndexes.first <= headingColumns ) {
+	if ( headingColumns && removedColumnIndexes.first < headingColumns ) {
 		const headingsRemoved = Math.min( headingColumns - 1 /* Other numbers are 0-based */, removedColumnIndexes.last ) -
 			removedColumnIndexes.first + 1;
 

From 627c61e07309cc6a1792d4d05071aa2e71e50fe0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20Go=C5=82aszewski?= <jodator@jodator.net>
Date: Wed, 8 Apr 2020 12:22:26 +0200
Subject: [PATCH 10/11] Fix tables used in tests.

---
 .../ckeditor5-table/tests/commands/removecolumncommand.js     | 4 ++--
 packages/ckeditor5-table/tests/tableutils.js                  | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/packages/ckeditor5-table/tests/commands/removecolumncommand.js b/packages/ckeditor5-table/tests/commands/removecolumncommand.js
index 905727c963e..487a2f16d9f 100644
--- a/packages/ckeditor5-table/tests/commands/removecolumncommand.js
+++ b/packages/ckeditor5-table/tests/commands/removecolumncommand.js
@@ -368,7 +368,7 @@ describe( 'RemoveColumnCommand', () => {
 		it( 'should decrease colspan of table cells from previous column', () => {
 			setData( model, modelTable( [
 				[ { colspan: 4, contents: '00' }, '04' ],
-				[ { colspan: 3, contents: '10' }, '14' ],
+				[ { colspan: 3, contents: '10' }, '13', '14' ],
 				[ { colspan: 2, contents: '20' }, '22[]', '23', '24' ],
 				[ '30', { colspan: 2, contents: '31' }, '33', '34' ],
 				[ '40', '41', '42', '43', '44' ]
@@ -378,7 +378,7 @@ describe( 'RemoveColumnCommand', () => {
 
 			assertEqualMarkup( getData( model ), modelTable( [
 				[ { colspan: 3, contents: '00' }, '04' ],
-				[ { colspan: 2, contents: '10' }, '14' ],
+				[ { colspan: 2, contents: '10' }, '13', '14' ],
 				[ { colspan: 2, contents: '20' }, '[]23', '24' ],
 				[ '30', '31', '33', '34' ],
 				[ '40', '41', '43', '44' ]
diff --git a/packages/ckeditor5-table/tests/tableutils.js b/packages/ckeditor5-table/tests/tableutils.js
index b8930c8cc84..ae1c4f56fab 100644
--- a/packages/ckeditor5-table/tests/tableutils.js
+++ b/packages/ckeditor5-table/tests/tableutils.js
@@ -1014,7 +1014,7 @@ describe( 'TableUtils', () => {
 			it( 'should decrease colspan of table cells from previous column', () => {
 				setData( model, modelTable( [
 					[ { colspan: 4, contents: '00' }, '04' ],
-					[ { colspan: 3, contents: '10' }, '14' ],
+					[ { colspan: 3, contents: '10' }, '13', '14' ],
 					[ { colspan: 2, contents: '20' }, '22', '23', '24' ],
 					[ '30', { colspan: 2, contents: '31' }, '33', '34' ],
 					[ '40', '41', '42', '43', '44' ]
@@ -1024,7 +1024,7 @@ describe( 'TableUtils', () => {
 
 				assertEqualMarkup( getData( model, { withoutSelection: true } ), modelTable( [
 					[ { colspan: 3, contents: '00' }, '04' ],
-					[ { colspan: 2, contents: '10' }, '14' ],
+					[ { colspan: 2, contents: '10' }, '13', '14' ],
 					[ { colspan: 2, contents: '20' }, '23', '24' ],
 					[ '30', '31', '33', '34' ],
 					[ '40', '41', '43', '44' ]

From 2a09cf10d86b6fa1a600d2fe14ff8558704060c9 Mon Sep 17 00:00:00 2001
From: Aleksander Nowodzinski <a.nowodzinski@cksource.com>
Date: Wed, 8 Apr 2020 14:13:47 +0200
Subject: [PATCH 11/11] Update src/tableutils.js

---
 packages/ckeditor5-table/src/tableutils.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/ckeditor5-table/src/tableutils.js b/packages/ckeditor5-table/src/tableutils.js
index f1a283276f3..a1e1b17bd66 100644
--- a/packages/ckeditor5-table/src/tableutils.js
+++ b/packages/ckeditor5-table/src/tableutils.js
@@ -310,7 +310,7 @@ export default class TableUtils extends Plugin {
 	/**
 	 * Removes columns from the given `table`.
 	 *
-	 * This method re-calculates the table geometry including `colspan` attribute of table cells overlapping removed columns
+	 * This method re-calculates the table geometry including the `colspan` attribute of table cells overlapping removed columns
 	 * and table headings values.
 	 *
 	 *		editor.plugins.get( 'TableUtils' ).removeColumns( table, { at: 1, columns: 2 } );