diff --git a/src/tsconfig.strictNullChecks.json b/src/tsconfig.strictNullChecks.json
index 18158fefc1f..87a7602d67a 100644
--- a/src/tsconfig.strictNullChecks.json
+++ b/src/tsconfig.strictNullChecks.json
@@ -330,6 +330,7 @@
 		"./vs/editor/contrib/hover/hoverWidgets.ts",
 		"./vs/editor/contrib/hover/modesGlyphHover.ts",
 		"./vs/editor/contrib/inPlaceReplace/inPlaceReplaceCommand.ts",
+		"./vs/editor/contrib/indentation/indentation.ts",
 		"./vs/editor/contrib/indentation/indentUtils.ts",
 		"./vs/editor/contrib/linesOperations/copyLinesCommand.ts",
 		"./vs/editor/contrib/linesOperations/deleteLinesCommand.ts",
diff --git a/src/vs/editor/contrib/indentation/indentation.ts b/src/vs/editor/contrib/indentation/indentation.ts
index ca4ac2590ab..85963260837 100644
--- a/src/vs/editor/contrib/indentation/indentation.ts
+++ b/src/vs/editor/contrib/indentation/indentation.ts
@@ -10,11 +10,11 @@ import { ICodeEditor } from 'vs/editor/browser/editorBrowser';
 import { EditorAction, IActionOptions, ServicesAccessor, registerEditorAction, registerEditorContribution } from 'vs/editor/browser/editorExtensions';
 import { ShiftCommand } from 'vs/editor/common/commands/shiftCommand';
 import { EditOperation } from 'vs/editor/common/core/editOperation';
-import { Range } from 'vs/editor/common/core/range';
+import { Range, IRange } from 'vs/editor/common/core/range';
 import { Selection } from 'vs/editor/common/core/selection';
 import { ICommand, ICursorStateComputerData, IEditOperationBuilder, IEditorContribution } from 'vs/editor/common/editorCommon';
 import { EditorContextKeys } from 'vs/editor/common/editorContextKeys';
-import { IIdentifiedSingleEditOperation, ITextModel } from 'vs/editor/common/model';
+import { IIdentifiedSingleEditOperation, ITextModel, EndOfLineSequence } from 'vs/editor/common/model';
 import { TextModel } from 'vs/editor/common/model/textModel';
 import { StandardTokenType, TextEdit } from 'vs/editor/common/modes';
 import { LanguageConfigurationRegistry } from 'vs/editor/common/modes/languageConfigurationRegistry';
@@ -48,12 +48,12 @@ export function unshiftIndent(tabSize: number, indentation: string, count?: numb
 export function getReindentEditOperations(model: ITextModel, startLineNumber: number, endLineNumber: number, inheritedIndent?: string): IIdentifiedSingleEditOperation[] {
 	if (model.getLineCount() === 1 && model.getLineMaxColumn(1) === 1) {
 		// Model is empty
-		return undefined;
+		return [];
 	}
 
 	let indentationRules = LanguageConfigurationRegistry.getIndentationRules(model.getLanguageIdentifier().id);
 	if (!indentationRules) {
-		return undefined;
+		return [];
 	}
 
 	endLineNumber = Math.min(endLineNumber, model.getLineCount());
@@ -73,7 +73,7 @@ export function getReindentEditOperations(model: ITextModel, startLineNumber: nu
 	}
 
 	if (startLineNumber > endLineNumber - 1) {
-		return undefined;
+		return [];
 	}
 
 	let { tabSize, insertSpaces } = model.getOptions();
@@ -167,7 +167,11 @@ export class IndentationToSpacesAction extends EditorAction {
 			return;
 		}
 		let modelOpts = model.getOptions();
-		const command = new IndentationToSpacesCommand(editor.getSelection(), modelOpts.tabSize);
+		let selection = editor.getSelection();
+		if (!selection) {
+			return;
+		}
+		const command = new IndentationToSpacesCommand(selection, modelOpts.tabSize);
 
 		editor.pushUndoStop();
 		editor.executeCommands(this.id, [command]);
@@ -197,7 +201,11 @@ export class IndentationToTabsAction extends EditorAction {
 			return;
 		}
 		let modelOpts = model.getOptions();
-		const command = new IndentationToTabsCommand(editor.getSelection(), modelOpts.tabSize);
+		let selection = editor.getSelection();
+		if (!selection) {
+			return;
+		}
+		const command = new IndentationToTabsCommand(selection, modelOpts.tabSize);
 
 		editor.pushUndoStop();
 		editor.executeCommands(this.id, [command]);
@@ -229,7 +237,7 @@ export class ChangeIndentationSizeAction extends EditorAction {
 			id: n.toString(),
 			label: n.toString(),
 			// add description for tabSize value set in the configuration
-			description: n === creationOpts.tabSize ? nls.localize('configuredTabSize', "Configured Tab Size") : null
+			description: n === creationOpts.tabSize ? nls.localize('configuredTabSize', "Configured Tab Size") : undefined
 		}));
 
 		// auto focus the tabSize set for the current editor
@@ -238,10 +246,12 @@ export class ChangeIndentationSizeAction extends EditorAction {
 		setTimeout(() => {
 			quickInputService.pick(picks, { placeHolder: nls.localize({ key: 'selectTabWidth', comment: ['Tab corresponds to the tab key'] }, "Select Tab Size for Current File"), activeItem: picks[autoFocusIndex] }).then(pick => {
 				if (pick) {
-					model.updateOptions({
-						tabSize: parseInt(pick.label, 10),
-						insertSpaces: this.insertSpaces
-					});
+					if (model && !model.isDisposed()) {
+						model.updateOptions({
+							tabSize: parseInt(pick.label, 10),
+							insertSpaces: this.insertSpaces
+						});
+					}
 				}
 			});
 		}, 50/* quick open is sensitive to being opened so soon after another */);
@@ -318,7 +328,7 @@ export class ReindentLinesAction extends EditorAction {
 			return;
 		}
 		let edits = getReindentEditOperations(model, 1, model.getLineCount());
-		if (edits) {
+		if (edits.length > 0) {
 			editor.pushUndoStop();
 			editor.executeEdits(this.id, edits);
 			editor.pushUndoStop();
@@ -342,9 +352,14 @@ export class ReindentSelectedLinesAction extends EditorAction {
 			return;
 		}
 
+		let selections = editor.getSelections();
+		if (selections === null) {
+			return;
+		}
+
 		let edits: IIdentifiedSingleEditOperation[] = [];
 
-		for (let selection of editor.getSelections()) {
+		for (let selection of selections) {
 			let startLineNumber = selection.startLineNumber;
 			let endLineNumber = selection.endLineNumber;
 
@@ -360,7 +375,7 @@ export class ReindentSelectedLinesAction extends EditorAction {
 				startLineNumber--;
 			}
 
-			let editOperations = getReindentEditOperations(model, startLineNumber, endLineNumber) || [];
+			let editOperations = getReindentEditOperations(model, startLineNumber, endLineNumber);
 			edits.push(...editOperations);
 		}
 
@@ -374,7 +389,7 @@ export class ReindentSelectedLinesAction extends EditorAction {
 
 export class AutoIndentOnPasteCommand implements ICommand {
 
-	private _edits: TextEdit[];
+	private _edits: { range: IRange; text: string; eol?: EndOfLineSequence; }[];
 
 	private _initialSelection: Selection;
 	private _selectionId: string;
@@ -385,7 +400,7 @@ export class AutoIndentOnPasteCommand implements ICommand {
 
 		for (let edit of edits) {
 			if (edit.range && typeof edit.text === 'string') {
-				this._edits.push(edit);
+				this._edits.push(edit as { range: IRange; text: string; eol?: EndOfLineSequence; });
 			}
 		}
 	}
@@ -456,11 +471,16 @@ export class AutoIndentOnPaste implements IEditorContribution {
 	}
 
 	private trigger(range: Range): void {
-		if (this.editor.getSelections().length > 1) {
+		let selections = this.editor.getSelections();
+		if (selections === null || selections.length > 1) {
 			return;
 		}
 
 		const model = this.editor.getModel();
+		if (!model) {
+			return;
+		}
+
 		if (!model.isCheapToTokenize(range.getStartPosition().lineNumber)) {
 			return;
 		}
@@ -588,7 +608,7 @@ export class AutoIndentOnPaste implements IEditorContribution {
 			}
 		}
 
-		let cmd = new AutoIndentOnPasteCommand(textEdits, this.editor.getSelection());
+		let cmd = new AutoIndentOnPasteCommand(textEdits, this.editor.getSelection()!);
 		this.editor.executeCommand('autoIndentOnPaste', cmd);
 		this.editor.pushUndoStop();
 	}