[New] prop-types: add support for PropTypes.exact

Closes #2590.

Author: jzabala

lib/util/propTypes.js

@@ -422,13 +422,14 @@ module.exports = function propTypesInstructions(context, components, utils) {
       const callName = value.callee.property.name;
       const argument = value.arguments[0];
       switch (callName) {
-        case 'shape': {
+        case 'shape':
+        case 'exact': {
           if (argument.type !== 'ObjectExpression') {
             // Invalid proptype or cannot analyse statically
             return {};
           }
           const shapeTypeDefinition = {
-            type: 'shape',
+            type: callName,
             children: {}
           };
           iterateProperties(context, argument.properties, (childKey, childValue, propNode) => {

tests/lib/rules/prop-types.js

@@ -5827,6 +5827,70 @@ ruleTester.run('prop-types', rule, {
         errors: [{
           message: '\'dateCreated\' is missing in props validation'
         }]
+      },
+      {
+        code: `
+          function Zoo(props) {
+            return (
+              <>
+                {props.foo.c}
+              </>
+            );
+          }
+
+          Zoo.propTypes = {
+            foo: PropTypes.exact({
+              a: PropTypes.number,
+              b: PropTypes.number,
+            }),
+          };
+        `,
+        errors: [{
+          message: "'foo.c' is missing in props validation"
+        }]
+      },
+      {
+        code: `
+          function Zoo(props) {
+            return (
+              <>
+                {props.foo.c}
+              </>
+            );
+          }
+
+          Zoo.propTypes = {
+            foo: React.PropTypes.exact({
+              a: PropTypes.number,
+              b: PropTypes.number,
+            }),
+          };
+        `,
+        errors: [{
+          message: "'foo.c' is missing in props validation"
+        }]
+      },
+      {
+        code: `
+          function Zoo(props) {
+            return (
+              <>
+                {props.foo.c}
+              </>
+            );
+          }
+
+          Zoo.propTypes = {
+            foo: Foo.PropTypes.exact({
+              a: PropTypes.number,
+              b: PropTypes.number,
+            }),
+          };
+        `,
+        settings,
+        errors: [{
+          message: "'foo.c' is missing in props validation"
+        }]
       }
     ])
   )