diff --git a/src/language-js/printer-estree.js b/src/language-js/printer-estree.js
index 8f4477047..1c16f6784 100644
--- a/src/language-js/printer-estree.js
+++ b/src/language-js/printer-estree.js
@@ -487,13 +487,37 @@ function printPathNoParens(path, options, print, args) {
         " = ",
         path.call(print, "right")
       ]);
-    case "TSTypeAssertionExpression":
-      return concat([
-        "<",
-        path.call(print, "typeAnnotation"),
-        ">",
-        path.call(print, "expression")
+    case "TSTypeAssertionExpression": {
+      const shouldBreakAfterCast = !(
+        n.expression.type === "ArrayExpression" ||
+        n.expression.type === "ObjectExpression"
+      );
+
+      const castGroup = group(
+        concat([
+          "<",
+          indent(concat([softline, path.call(print, "typeAnnotation")])),
+          softline,
+          ">"
+        ])
+      );
+
+      const exprContents = concat([
+        ifBreak("("),
+        indent(concat([softline, path.call(print, "expression")])),
+        softline,
+        ifBreak(")")
       ]);
+
+      if (shouldBreakAfterCast) {
+        return conditionalGroup([
+          concat([castGroup, path.call(print, "expression")]),
+          concat([castGroup, group(exprContents, { shouldBreak: true })]),
+          concat([castGroup, path.call(print, "expression")])
+        ]);
+      }
+      return group(concat([castGroup, path.call(print, "expression")]));
+    }
     case "MemberExpression": {
       const parent = path.getParentNode();
       let firstNonMemberParent;
@@ -2506,6 +2530,7 @@ function printPathNoParens(path, options, print, args) {
       // | C
 
       const parent = path.getParentNode();
+      const parentParent = path.getParentNode(1);
 
       // If there's a leading comment, the parent is doing the indentation
       const shouldIndent =
@@ -2514,6 +2539,8 @@ function printPathNoParens(path, options, print, args) {
         parent.type !== "GenericTypeAnnotation" &&
         parent.type !== "TSTypeReference" &&
         !(parent.type === "FunctionTypeParam" && !parent.name) &&
+        parentParent.type !== "TSTypeAssertionExpression" &&
+
         !(
           (parent.type === "TypeAlias" ||
             parent.type === "VariableDeclarator") &&
diff --git a/tests/typescript_cast/__snapshots__/jsfmt.spec.js.snap b/tests/typescript_cast/__snapshots__/jsfmt.spec.js.snap
index e6caf614b..a5e4244b6 100644
--- a/tests/typescript_cast/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/typescript_cast/__snapshots__/jsfmt.spec.js.snap
@@ -1,5 +1,251 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`generic-cast.ts 1`] = `
+// https://github.com/prettier/prettier/issues/4171
+function y() {
+
+  const fits = <Immutable.Map<string, any>>fits();
+  const fitsObjLiteral = <Immutable.Map<string, any>>{ a: "test" };
+  const fitsArrayLiteral = <Immutable.Map<string, any>>["test", "test2"]
+
+  const breakAfterCast = <Immutable.Map<string, any>>someExistingConfigMap.mergeDeep(fallbackOpts);
+
+  const stillTooLong = <Immutable.Map<string, boolean, number, object, null, undefined, any, void, never>>someExistingConfigMap.mergeDeep(fallbackOptions);
+
+  const stillTooLong2 = <Immutable.Map<string, boolean, number, object, null, undefined, any, void, never> | undefined>someExistingConfigMap.mergeDeep(fallbackOptions);
+
+  const stillTooLong3 = <Immutable.Map<string>>someExistingConfigMap.mergeDeep(fallbackOptions.someMethodWithLongName(param1, param2));
+
+  const stillTooLong4 = <Immutable.Map<string, boolean, number, object, null, undefined, any, void, never> | undefined>someExistingConfigMap.mergeDeep(fallbackOptions.someMethodWithLongName(param1, param2));
+  
+  const testObjLiteral = <Immutable.Map<string, any>>{ property1: "myPropertyVal" };
+
+  const testObjLiteral2 = <Immutable.Map<string, any, number, boolean, object, null, undefined, never, "extra long">>{ property1: "myPropertyVal" };
+
+  const testArrayLiteral = <Immutable.Map<string, any>>["first", "second", "third"];
+
+  const testArrayLiteral2 = <Immutable.Map<string, any, number, boolean, object, null, undefined, never, "extra long">>["first", "second", "third"];
+
+  const insideFuncCall = myFunc(param1, <Immutable.Map<string, any>>param2, param3)
+}
+
+// https://github.com/prettier/prettier/issues/4168
+function x() {
+  const fits = <PermissionsChecker<any> | undefined>(<any>permissions)[type];
+  const fitsObjLiteral = <PermissionsChecker<any> | undefined>{ a: "test" };
+  const fitsArrayLiteral = <PermissionsChecker<any> | undefined>["t1", "t2"];
+
+  const breakAfterCast = <PermissionsChecker<any> | undefined>(<any>permissions)[receiverType];
+
+  const stillTooLong = <PermissionsChecker<object> | undefined | number | string | boolean>(<any>permissions)[receiverType];
+
+  const stillTooLong2 = <PermissionsChecker<object> | undefined | number | string | boolean | null | never>(<any>permissions)[receiverType];
+
+  const stillTooLong3 = <PermissionsChecker<object> | undefined>(<any>permissions.someMethodWithLongName(parameter1, parameter2))[receiverTypeLongName];
+
+  const stillTooLong4 = <PermissionsChecker<object> | undefined | number | string | boolean | null | never>(<any>permissions.someMethodWithLongName(parameter1, parameter2))[receiverTypeLongName];
+
+  const testObjLiteral =  <PermissionsChecker<any> | undefined>{ prop1: "myPropVal" };
+
+  const testObjLiteral2 = <PermissionsChecker<object> | undefined | number | string | boolean | null | never | object>{ prop1: "myPropVal" };
+
+  const testArrayLiteral = <PermissionsChecker<any> | undefined>["first", "second", "third"];
+
+  const testArrayLiteral2 = <PermissionsChecker<object> | undefined | number | string | boolean | null | never | object>["first", "second", "third"];
+
+  const insideFuncCall = myFunc(param1, <PermissionsChecker<any> | undefined>param2, param3)
+}
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+// https://github.com/prettier/prettier/issues/4171
+function y() {
+  const fits = <Immutable.Map<string, any>>fits();
+  const fitsObjLiteral = <Immutable.Map<string, any>>{ a: "test" };
+  const fitsArrayLiteral = <Immutable.Map<string, any>>["test", "test2"];
+
+  const breakAfterCast = <Immutable.Map<string, any>>(
+    someExistingConfigMap.mergeDeep(fallbackOpts)
+  );
+
+  const stillTooLong = <
+    Immutable.Map<
+      string,
+      boolean,
+      number,
+      object,
+      null,
+      undefined,
+      any,
+      void,
+      never
+    >
+  >someExistingConfigMap.mergeDeep(fallbackOptions);
+
+  const stillTooLong2 = <
+    | Immutable.Map<
+        string,
+        boolean,
+        number,
+        object,
+        null,
+        undefined,
+        any,
+        void,
+        never
+      >
+    | undefined
+  >someExistingConfigMap.mergeDeep(fallbackOptions);
+
+  const stillTooLong3 = <Immutable.Map<string>>(
+    someExistingConfigMap.mergeDeep(
+      fallbackOptions.someMethodWithLongName(param1, param2)
+    )
+  );
+
+  const stillTooLong4 = <
+    | Immutable.Map<
+        string,
+        boolean,
+        number,
+        object,
+        null,
+        undefined,
+        any,
+        void,
+        never
+      >
+    | undefined
+  >someExistingConfigMap.mergeDeep(
+    fallbackOptions.someMethodWithLongName(param1, param2)
+  );
+
+  const testObjLiteral = <Immutable.Map<string, any>>{
+    property1: "myPropertyVal"
+  };
+
+  const testObjLiteral2 = <
+    Immutable.Map<
+      string,
+      any,
+      number,
+      boolean,
+      object,
+      null,
+      undefined,
+      never,
+      "extra long"
+    >
+  >{ property1: "myPropertyVal" };
+
+  const testArrayLiteral = <Immutable.Map<string, any>>[
+    "first",
+    "second",
+    "third"
+  ];
+
+  const testArrayLiteral2 = <
+    Immutable.Map<
+      string,
+      any,
+      number,
+      boolean,
+      object,
+      null,
+      undefined,
+      never,
+      "extra long"
+    >
+  >["first", "second", "third"];
+
+  const insideFuncCall = myFunc(
+    param1,
+    <Immutable.Map<string, any>>param2,
+    param3
+  );
+}
+
+// https://github.com/prettier/prettier/issues/4168
+function x() {
+  const fits = <PermissionsChecker<any> | undefined>(<any>permissions)[type];
+  const fitsObjLiteral = <PermissionsChecker<any> | undefined>{ a: "test" };
+  const fitsArrayLiteral = <PermissionsChecker<any> | undefined>["t1", "t2"];
+
+  const breakAfterCast = <PermissionsChecker<any> | undefined>(
+    (<any>permissions)[receiverType]
+  );
+
+  const stillTooLong = <
+    PermissionsChecker<object> | undefined | number | string | boolean
+  >(<any>permissions)[receiverType];
+
+  const stillTooLong2 = <
+    | PermissionsChecker<object>
+    | undefined
+    | number
+    | string
+    | boolean
+    | null
+    | never
+  >(<any>permissions)[receiverType];
+
+  const stillTooLong3 = <PermissionsChecker<object> | undefined>(
+    (<any>permissions.someMethodWithLongName(parameter1, parameter2))[
+      receiverTypeLongName
+    ]
+  );
+
+  const stillTooLong4 = <
+    | PermissionsChecker<object>
+    | undefined
+    | number
+    | string
+    | boolean
+    | null
+    | never
+  >(<any>permissions.someMethodWithLongName(parameter1, parameter2))[
+    receiverTypeLongName
+  ];
+
+  const testObjLiteral = <PermissionsChecker<any> | undefined>{
+    prop1: "myPropVal"
+  };
+
+  const testObjLiteral2 = <
+    | PermissionsChecker<object>
+    | undefined
+    | number
+    | string
+    | boolean
+    | null
+    | never
+    | object
+  >{ prop1: "myPropVal" };
+
+  const testArrayLiteral = <PermissionsChecker<any> | undefined>[
+    "first",
+    "second",
+    "third"
+  ];
+
+  const testArrayLiteral2 = <
+    | PermissionsChecker<object>
+    | undefined
+    | number
+    | string
+    | boolean
+    | null
+    | never
+    | object
+  >["first", "second", "third"];
+
+  const insideFuncCall = myFunc(
+    param1,
+    <PermissionsChecker<any> | undefined>param2,
+    param3
+  );
+}
+
+`;
+
 exports[`hug-args.ts 1`] = `
 postMessage(
   <IActionMessage>{
diff --git a/tests/typescript_cast/generic-cast.ts b/tests/typescript_cast/generic-cast.ts
new file mode 100644
index 000000000..8c5231293
--- /dev/null
+++ b/tests/typescript_cast/generic-cast.ts
@@ -0,0 +1,54 @@
+// https://github.com/prettier/prettier/issues/4171
+function y() {
+
+  const fits = <Immutable.Map<string, any>>fits();
+  const fitsObjLiteral = <Immutable.Map<string, any>>{ a: "test" };
+  const fitsArrayLiteral = <Immutable.Map<string, any>>["test", "test2"]
+
+  const breakAfterCast = <Immutable.Map<string, any>>someExistingConfigMap.mergeDeep(fallbackOpts);
+
+  const stillTooLong = <Immutable.Map<string, boolean, number, object, null, undefined, any, void, never>>someExistingConfigMap.mergeDeep(fallbackOptions);
+
+  const stillTooLong2 = <Immutable.Map<string, boolean, number, object, null, undefined, any, void, never> | undefined>someExistingConfigMap.mergeDeep(fallbackOptions);
+
+  const stillTooLong3 = <Immutable.Map<string>>someExistingConfigMap.mergeDeep(fallbackOptions.someMethodWithLongName(param1, param2));
+
+  const stillTooLong4 = <Immutable.Map<string, boolean, number, object, null, undefined, any, void, never> | undefined>someExistingConfigMap.mergeDeep(fallbackOptions.someMethodWithLongName(param1, param2));
+  
+  const testObjLiteral = <Immutable.Map<string, any>>{ property1: "myPropertyVal" };
+
+  const testObjLiteral2 = <Immutable.Map<string, any, number, boolean, object, null, undefined, never, "extra long">>{ property1: "myPropertyVal" };
+
+  const testArrayLiteral = <Immutable.Map<string, any>>["first", "second", "third"];
+
+  const testArrayLiteral2 = <Immutable.Map<string, any, number, boolean, object, null, undefined, never, "extra long">>["first", "second", "third"];
+
+  const insideFuncCall = myFunc(param1, <Immutable.Map<string, any>>param2, param3)
+}
+
+// https://github.com/prettier/prettier/issues/4168
+function x() {
+  const fits = <PermissionsChecker<any> | undefined>(<any>permissions)[type];
+  const fitsObjLiteral = <PermissionsChecker<any> | undefined>{ a: "test" };
+  const fitsArrayLiteral = <PermissionsChecker<any> | undefined>["t1", "t2"];
+
+  const breakAfterCast = <PermissionsChecker<any> | undefined>(<any>permissions)[receiverType];
+
+  const stillTooLong = <PermissionsChecker<object> | undefined | number | string | boolean>(<any>permissions)[receiverType];
+
+  const stillTooLong2 = <PermissionsChecker<object> | undefined | number | string | boolean | null | never>(<any>permissions)[receiverType];
+
+  const stillTooLong3 = <PermissionsChecker<object> | undefined>(<any>permissions.someMethodWithLongName(parameter1, parameter2))[receiverTypeLongName];
+
+  const stillTooLong4 = <PermissionsChecker<object> | undefined | number | string | boolean | null | never>(<any>permissions.someMethodWithLongName(parameter1, parameter2))[receiverTypeLongName];
+
+  const testObjLiteral =  <PermissionsChecker<any> | undefined>{ prop1: "myPropVal" };
+
+  const testObjLiteral2 = <PermissionsChecker<object> | undefined | number | string | boolean | null | never | object>{ prop1: "myPropVal" };
+
+  const testArrayLiteral = <PermissionsChecker<any> | undefined>["first", "second", "third"];
+
+  const testArrayLiteral2 = <PermissionsChecker<object> | undefined | number | string | boolean | null | never | object>["first", "second", "third"];
+
+  const insideFuncCall = myFunc(param1, <PermissionsChecker<any> | undefined>param2, param3)
+}