[enzyme-adapter-react-{16,16.3}] [new] support shallow rendering `cre…

…ateContext()` providers and consumers
enzymejs · Jan 22, 2019 · 107a3f4 · 107a3f4
1 parent 2a00a00
commit 107a3f4
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Showing 2 changed files with 75 additions and 4 deletions.
diff --git a/packages/enzyme-adapter-react-16.3/src/ReactSixteenThreeAdapter.js b/packages/enzyme-adapter-react-16.3/src/ReactSixteenThreeAdapter.js
@@ -14,6 +14,8 @@ import {
   isPortal,
   isForwardRef,
   isValidElementType,
+  isContextProvider,
+  isContextConsumer,
   AsyncMode,
   Fragment,
   ContextConsumer,
@@ -327,11 +329,29 @@ class ReactSixteenThreeAdapter extends EnzymeAdapter {
     let isDOM = false;
     let cachedNode = null;
     return {
-      render(el, context) {
+      render(el, context, {
+        providerValues = new Map(),
+      } = {}) {
         cachedNode = el;
         /* eslint consistent-return: 0 */
         if (typeof el.type === 'string') {
           isDOM = true;
+        } else if (isContextProvider(el)) {
+          providerValues.set(el.type, el.props.value);
+          const MockProvider = Object.assign(
+            props => props.children,
+            el.type,
+          );
+          return withSetStateAllowed(() => renderer.render({ ...el, type: MockProvider }));
+        } else if (isContextConsumer(el)) {
+          const value = providerValues.has(el.type.Provider)
+            ? providerValues.get(el.type.Provider)
+            : el.type.Provider._context._defaultValue;
+          const MockConsumer = Object.assign(
+            props => props.children(value),
+            el.type,
+          );
+          return withSetStateAllowed(() => renderer.render({ ...el, type: MockConsumer }));
         } else {
           isDOM = false;
           const { type: Component } = el;
@@ -508,7 +528,10 @@ class ReactSixteenThreeAdapter extends EnzymeAdapter {
     if (!inst || !this.isValidElement(inst)) {
       return false;
     }
-    return typeof inst.type === 'function' || isForwardRef(inst);
+    return typeof inst.type === 'function'
+      || isForwardRef(inst)
+      || isContextProvider(inst)
+      || isContextConsumer(inst);
   }
 
   createElement(...args) {

diff --git a/packages/enzyme-adapter-react-16/src/ReactSixteenAdapter.js b/packages/enzyme-adapter-react-16/src/ReactSixteenAdapter.js
@@ -14,6 +14,8 @@ import {
   isPortal,
   isForwardRef,
   isValidElementType,
+  isContextProvider,
+  isContextConsumer,
   AsyncMode,
   ConcurrentMode,
   Fragment,
@@ -252,6 +254,31 @@ function getEmptyStateValue() {
   return testRenderer._instance.state;
 }
 
+function getProviderFromConsumer(Consumer) {
+  // React stores references to the Provider on a Consumer differently across versions.
+  let Provider;
+  if (Consumer.Provider) {
+    ({ Provider } = Consumer);
+  } else if (Consumer._context) {
+    ({ Provider } = Consumer._context);
+  }
+  if (Provider) {
+    return Provider;
+  }
+  throw new Error('Enzyme Internal Error: can\'t figure out how to get Provider from Consumer');
+}
+
+function getProviderDefaultValue(Provider) {
+  // React stores references to the Provider's defaultValue differently across versions.
+  if ('_defaultValue' in Provider._context) {
+    return Provider._context._defaultValue;
+  }
+  if ('_currentValue' in Provider._context) {
+    return Provider._context._currentValue;
+  }
+  throw new Error('Enzyme Internal Error: can\'t figure out how to get Provider\'s default value');
+}
+
 class ReactSixteenAdapter extends EnzymeAdapter {
   constructor() {
     super();
@@ -350,11 +377,29 @@ class ReactSixteenAdapter extends EnzymeAdapter {
     let isDOM = false;
     let cachedNode = null;
     return {
-      render(el, unmaskedContext) {
+      render(el, unmaskedContext, {
+        providerValues = new Map(),
+      } = {}) {
         cachedNode = el;
         /* eslint consistent-return: 0 */
         if (typeof el.type === 'string') {
           isDOM = true;
+        } else if (isContextProvider(el)) {
+          providerValues.set(el.type, el.props.value);
+          const MockProvider = Object.assign(
+            props => props.children,
+            el.type,
+          );
+          return withSetStateAllowed(() => renderer.render({ ...el, type: MockProvider }));
+        } else if (isContextConsumer(el)) {
+          const Provider = getProviderFromConsumer(el.type);
+          const value = providerValues.has(Provider)
+            ? providerValues.get(Provider) : getProviderDefaultValue(Provider);
+          const MockConsumer = Object.assign(
+            props => props.children(value),
+            el.type,
+          );
+          return withSetStateAllowed(() => renderer.render({ ...el, type: MockConsumer }));
         } else {
           isDOM = false;
           const { type: Component } = el;
@@ -557,7 +602,10 @@ class ReactSixteenAdapter extends EnzymeAdapter {
     if (!inst || !this.isValidElement(inst)) {
       return false;
     }
-    return typeof inst.type === 'function' || isForwardRef(inst);
+    return typeof inst.type === 'function'
+      || isForwardRef(inst)
+      || isContextProvider(inst)
+      || isContextConsumer(inst);
   }
 
   createElement(...args) {