Fixed non-string labels (fixes #816).

CHANGELOG.md

@@ -1,3 +1,7 @@
+## Next
+
+- **Fixed:** Regression of accepting non-string labels in `useField` and `connectField`. [\#816](https://github.com/vazco/uniforms/issues/816)
+
 ## [v3.0.0-rc.5](https://github.com/vazco/uniforms/tree/v3.0.0-rc.5) (2020-09-30)
 
 - **Added:** New `disableItem` prop in `SelectField`. [\#736](https://github.com/vazco/uniforms/issues/736)

packages/uniforms/__tests__/connectField.tsx

@@ -1,4 +1,4 @@
-import React from 'react';
+import React, { ReactNode } from 'react';
 import { SimpleSchema } from 'simpl-schema';
 import { Context, connectField, randomIds } from 'uniforms';
 import { SimpleSchemaBridge } from 'uniforms-bridge-simple-schema';
@@ -125,4 +125,61 @@ describe('connectField', () => {
       expect(onChange).toBeCalledWith('field', 'initialValueExample');
     });
   });
+
+  // TODO: Write tests for `placeholder`.
+  describe('when rendered with label', () => {
+    const labelA = <span style={{ color: 'red' }}>Error</span>;
+    const labelB = <span style={{ color: 'green' }}>OK</span>;
+
+    it.each([
+      ['Props', '', false, 'Props'],
+      ['Props', '', true, 'Props'],
+      ['Props', 'Schema', false, 'Props'],
+      ['Props', 'Schema', true, 'Props'],
+      ['Props', labelB, false, 'Props'],
+      ['Props', labelB, true, 'Props'],
+      [false, '', false, ''],
+      [false, '', true, ''],
+      [false, 'Schema', false, ''],
+      [false, 'Schema', true, ''],
+      [false, labelB, false, ''],
+      [false, labelB, true, ''],
+      [labelA, '', false, labelA],
+      [labelA, '', true, labelA],
+      [labelA, 'Schema', false, labelA],
+      [labelA, 'Schema', true, labelA],
+      [labelA, labelB, false, labelA],
+      [labelA, labelB, true, labelA],
+      [true, '', false, ''],
+      [true, '', true, ''],
+      [true, 'Schema', false, 'Schema'],
+      [true, 'Schema', true, 'Schema'],
+      [true, labelB, false, labelB],
+      [true, labelB, true, labelB],
+      [undefined, '', false, ''],
+      [undefined, '', true, ''],
+      [undefined, 'Schema', false, ''],
+      [undefined, 'Schema', true, 'Schema'],
+      [undefined, labelB, false, ''],
+      [undefined, labelB, true, labelB],
+    ] as [ReactNode, ReactNode, boolean, ReactNode][])(
+      'resolves it correctly (%#)',
+      (prop, schema, state, result) => {
+        const context: typeof reactContext = {
+          context: {
+            ...reactContext.context,
+            state: { ...reactContext.context.state, label: state },
+          },
+        };
+
+        jest
+          .spyOn(context.context.schema, 'getProps')
+          .mockReturnValueOnce({ label: schema });
+
+        const Field = connectField(Test);
+        const wrapper = mount(<Field name="field" label={prop} />, context);
+        expect(wrapper.find(Test).prop('label')).toBe(result);
+      },
+    );
+  });
 });

packages/uniforms/src/useField.tsx

@@ -1,30 +1,31 @@
 import get from 'lodash/get';
 import mapValues from 'lodash/mapValues';
-import { useCallback, useEffect, useMemo } from 'react';
+import { ReactNode, useCallback, useEffect, useMemo } from 'react';
 
 import { joinName } from './joinName';
 import { GuaranteedProps } from './types';
 import { useForm } from './useForm';
 
 function propagate(
-  prop: unknown,
-  schema: unknown,
+  prop: ReactNode,
+  schema: ReactNode,
   state: boolean,
-  fallback: string,
-): [string, string] {
-  const schemaDisabled = schema === false || schema === '';
-  const schemaValue =
-    typeof schema === 'string' ? schema : schemaDisabled ? '' : fallback;
-  const resultValue =
-    typeof prop === 'string'
-      ? prop
-      : prop === null ||
-        prop === false ||
-        (prop === undefined && !state) ||
-        schemaDisabled
+  fallback: ReactNode,
+): [ReactNode, ReactNode] {
+  const forcedFallbackInProp = prop === true || prop === undefined;
+  const forcedFallbackInSchema = schema === true || schema === undefined;
+
+  const schemaValue = forcedFallbackInSchema ? fallback : schema;
+  const value =
+    prop === '' ||
+    prop === false ||
+    (forcedFallbackInProp && (forcedFallbackInSchema || !state))
       ? ''
-      : schemaValue;
-  return [resultValue, schemaValue];
+      : forcedFallbackInProp
+      ? schemaValue
+      : prop;
+
+  return [value, schemaValue];
 }
 
 export function useField<
@@ -112,7 +113,8 @@ export function useField<
     ...props,
     label,
     name,
-    placeholder,
+    // TODO: Should we assert `typeof placeholder === 'string'`?
+    placeholder: placeholder as string,
   };
 
   return [fieldProps, context] as [typeof fieldProps, typeof context];