diff --git a/src/explorer/Explorer.test.tsx b/src/explorer/Explorer.test.tsx
index c94c6b4d..533f86b1 100644
--- a/src/explorer/Explorer.test.tsx
+++ b/src/explorer/Explorer.test.tsx
@@ -6,7 +6,6 @@ import { cleanup } from '@testing-library/react';
 import userEvent from '@testing-library/user-event';
 import React from 'react';
 import { testRender, uuid } from '../../test';
-import { FileMetadata } from '../fileStorage/actions';
 import Explorer from './Explorer';
 import {
     explorerArchiveAllFiles,
@@ -15,6 +14,7 @@ import {
     explorerImportFiles,
     explorerRenameFile,
 } from './actions';
+import { ExplorerFileInfo } from './reducers';
 
 afterEach(async () => {
     jest.restoreAllMocks();
@@ -22,10 +22,9 @@ afterEach(async () => {
     localStorage.clear();
 });
 
-const testFile: FileMetadata = {
-    uuid: uuid(0),
-    path: 'test.file',
-    sha256: '',
+const testFile: ExplorerFileInfo = {
+    id: uuid(0),
+    name: 'test.file',
 };
 
 describe('archive button', () => {
diff --git a/src/explorer/Explorer.tsx b/src/explorer/Explorer.tsx
index 59a15701..38cda4d5 100644
--- a/src/explorer/Explorer.tsx
+++ b/src/explorer/Explorer.tsx
@@ -290,12 +290,12 @@ const FileTree: React.VoidFunctionComponent<FileTreeProps> = ({ i18n }) => {
         () =>
             files.reduce(
                 (obj, file) => {
-                    const index = file.uuid;
+                    const index = file.id;
 
                     obj[index] = {
                         index,
                         data: {
-                            fileName: file.path,
+                            fileName: file.name,
                             icon: 'document',
                             secondaryLabel: (
                                 <TreeItemContext.Consumer>
@@ -319,8 +319,8 @@ const FileTree: React.VoidFunctionComponent<FileTreeProps> = ({ i18n }) => {
                         hasChildren: true,
                         children: [...files]
                             // REVISIT: consider using Intl.Collator() for i18n.locale
-                            .sort((a, b) => a.path.localeCompare(b.path))
-                            .map((n) => n.uuid),
+                            .sort((a, b) => a.name.localeCompare(b.name))
+                            .map((n) => n.id),
                     },
                 } as Record<TreeItemIndex, FileTreeItem>,
             ),
diff --git a/src/explorer/newFileWizard/NewFileWizard.tsx b/src/explorer/newFileWizard/NewFileWizard.tsx
index d09b5bd0..3b47487e 100644
--- a/src/explorer/newFileWizard/NewFileWizard.tsx
+++ b/src/explorer/newFileWizard/NewFileWizard.tsx
@@ -45,7 +45,7 @@ const NewFileWizard: React.VoidFunctionComponent<NewFileWizardProps> = ({
     const fileNameValidation = validateFileName(
         fileName,
         pythonFileExtension,
-        files.map((f) => f.path),
+        files.map((f) => f.name),
     );
     const [hubType, setHubType] = useState(defaultHub);
 
diff --git a/src/explorer/reducers.test.ts b/src/explorer/reducers.test.ts
index f65e2c8c..ebc1ed7a 100644
--- a/src/explorer/reducers.test.ts
+++ b/src/explorer/reducers.test.ts
@@ -9,50 +9,84 @@ import {
     fileStorageDidInitialize,
     fileStorageDidRemoveItem,
 } from '../fileStorage/actions';
-import reducers from './reducers';
+import reducers, { ExplorerFileInfo } from './reducers';
 
 type State = ReturnType<typeof reducers>;
 
-test('files', () => {
-    const testFile: FileMetadata = {
+describe('files', () => {
+    const testFile: ExplorerFileInfo = {
+        id: uuid(0),
+        name: 'test.file',
+    };
+
+    const testFileMetadata: FileMetadata = {
         uuid: uuid(0),
         path: 'test.file',
         sha256: '',
     };
 
-    const modifiedFile: FileMetadata = { ...testFile, path: 'modified.file' };
+    const modifiedFile: ExplorerFileInfo = {
+        ...testFile,
+        name: 'modified.file',
+    };
 
-    expect(testFile).not.toEqual(modifiedFile);
+    const modifiedFileMetadata: FileMetadata = {
+        ...testFileMetadata,
+        path: 'modified.file',
+    };
 
-    // initialization populates file list
-    expect(
-        reducers(
-            { files: [] as readonly FileMetadata[] } as State,
-            fileStorageDidInitialize([testFile]),
-        ).files,
-    ).toEqual([testFile]);
+    beforeAll(() => {
+        // check validity of test data before starting tests
+        expect(testFile).not.toEqual(modifiedFile);
+        expect(testFileMetadata).not.toEqual(modifiedFileMetadata);
+    });
 
-    // adding appends an item
-    expect(
-        reducers(
-            { files: [] as readonly FileMetadata[] } as State,
-            fileStorageDidAddItem(testFile),
-        ).files,
-    ).toEqual([testFile]);
+    it('should get a list when file storage is initialized', () => {
+        expect(
+            reducers(
+                { files: [] as readonly ExplorerFileInfo[] } as State,
+                fileStorageDidInitialize([testFileMetadata]),
+            ).files,
+        ).toEqual([testFile]);
+    });
 
-    // changing replaces an item
-    expect(
-        reducers(
-            { files: [testFile] as readonly FileMetadata[] } as State,
-            fileStorageDidChangeItem(testFile, modifiedFile),
-        ).files,
-    ).toEqual([modifiedFile]);
+    it('should modify the list when a file is added to storage', () => {
+        expect(
+            reducers(
+                { files: [] as readonly ExplorerFileInfo[] } as State,
+                fileStorageDidAddItem(testFileMetadata),
+            ).files,
+        ).toEqual([testFile]);
+    });
 
-    // removing deletes an item
-    expect(
-        reducers(
-            { files: [testFile] as readonly FileMetadata[] } as State,
-            fileStorageDidRemoveItem(testFile),
-        ).files,
-    ).not.toContain(testFile);
+    it('should modify the list when an item is renamed in storage', () => {
+        expect(
+            reducers(
+                { files: [testFile] as readonly ExplorerFileInfo[] } as State,
+                fileStorageDidChangeItem(testFileMetadata, modifiedFileMetadata),
+            ).files,
+        ).toEqual([modifiedFile]);
+    });
+
+    it('should not modify the list if a change is made other than renaming', () => {
+        const originalList: readonly ExplorerFileInfo[] = [testFile];
+        expect(
+            reducers(
+                { files: originalList } as State,
+                fileStorageDidChangeItem(testFileMetadata, {
+                    ...testFileMetadata,
+                    sha256: 'changed',
+                }),
+            ).files,
+        ).toBe(originalList);
+    });
+
+    it('should modify the list when a file is removed from storage', () => {
+        expect(
+            reducers(
+                { files: [testFile] as readonly ExplorerFileInfo[] } as State,
+                fileStorageDidRemoveItem(testFileMetadata),
+            ).files,
+        ).not.toContain(testFile);
+    });
 });
diff --git a/src/explorer/reducers.ts b/src/explorer/reducers.ts
index d820af8c..cda4c2e7 100644
--- a/src/explorer/reducers.ts
+++ b/src/explorer/reducers.ts
@@ -12,21 +12,40 @@ import {
 
 import renameFileDialog from './renameFileDialog/reducers';
 
-const files: Reducer<readonly FileMetadata[]> = (state = [], action) => {
+export type ExplorerFileInfo = Readonly<{
+    /** A unique identifier for this file (not the path, which can change). */
+    id: string;
+    /** The file name (including extension - without directory). */
+    name: string;
+}>;
+
+function metadataToInfo(file: FileMetadata): ExplorerFileInfo {
+    return { id: file.uuid, name: file.path };
+}
+
+const files: Reducer<readonly ExplorerFileInfo[]> = (state = [], action) => {
     if (fileStorageDidInitialize.matches(action)) {
-        return [...action.files];
+        return action.files.map(metadataToInfo);
     }
 
     if (fileStorageDidAddItem.matches(action)) {
-        return [...state, action.file];
+        return [...state, metadataToInfo(action.file)];
     }
 
     if (fileStorageDidChangeItem.matches(action)) {
-        return [...state].map((f) => (f.uuid === action.file.uuid ? action.file : f));
+        // We only care about UUID and the path. UUID can't change so if the
+        // path didn't change, there is nothing to do.
+        if (action.oldFile.path === action.file.path) {
+            return state;
+        }
+
+        return state.map((f) =>
+            f.id === action.file.uuid ? metadataToInfo(action.file) : f,
+        );
     }
 
     if (fileStorageDidRemoveItem.matches(action)) {
-        return [...state].filter((value) => value.uuid !== action.file.uuid);
+        return state.filter((value) => value.id !== action.file.uuid);
     }
 
     return state;
diff --git a/src/explorer/renameFileDialog/RenameFileDialog.tsx b/src/explorer/renameFileDialog/RenameFileDialog.tsx
index 34ba7672..bfabcf0a 100644
--- a/src/explorer/renameFileDialog/RenameFileDialog.tsx
+++ b/src/explorer/renameFileDialog/RenameFileDialog.tsx
@@ -28,7 +28,7 @@ const RenameFileDialog: React.VFC = () => {
     const result = validateFileName(
         newName,
         extension,
-        files.map((f) => f.path),
+        files.map((f) => f.name),
     );
 
     const inputRef = useRef<HTMLInputElement>(null);
diff --git a/src/explorer/sagas.ts b/src/explorer/sagas.ts
index bcfc7e47..bff37894 100644
--- a/src/explorer/sagas.ts
+++ b/src/explorer/sagas.ts
@@ -125,7 +125,7 @@ function* handleExplorerImportFiles(): Generator {
             const result = validateFileName(
                 baseName,
                 pythonFileExtension,
-                existingFiles.map((f) => f.path),
+                existingFiles.map((f) => f.name),
             );
 
             if (result != FileNameValidationResult.IsOk) {