Do not break long `describe` calls (#953)

This ensures that `describe` calls in test suites are whitelisted in the same way as `it` and `test` and never break across lines.

src/printer.js

@@ -636,9 +636,12 @@ function genericPrintNoParens(path, options, print) {
       if (
         // We want to keep require calls as a unit
         (n.callee.type === "Identifier" && n.callee.name === "require") ||
-        // `it('long name', () => {` should not break
+        // Keep test declarations on a single line
+        // e.g. `it('long name', () => {`
         (n.callee.type === "Identifier" &&
-          (n.callee.name === "it" || n.callee.name === "test") &&
+          (n.callee.name === "it" ||
+            n.callee.name === "test" ||
+            n.callee.name === "describe") &&
           n.arguments.length === 2 &&
           (n.arguments[0].type === "StringLiteral" ||
             n.arguments[0].type === "TemplateLiteral" ||

tests/test_declarations/__snapshots__/jsfmt.spec.js.snap

@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`it.js 1`] = `
+exports[`test_declarations.js 1`] = `
 "// Shouldn't break
 
 it(\\"does something really long and complicated so I have to write a very long name for the test\\", () => {
@@ -34,6 +34,18 @@ test(\`does something really long and complicated so I have to write a very long
   console.log(\\"hello!\\");
 });
 
+describe(\\"does something really long and complicated so I have to write a very long name for the describe block\\", () => {
+  it(\\"an example test\\", (done) => {
+    console.log(\\"hello!\\");
+  });
+});
+
+describe(\`does something really long and complicated so I have to write a very long name for the describe block\`, () => {
+  it(\`an example test\`, (done) => {
+    console.log(\\"hello!\\");
+  });
+});
+
 // Should break
 
 it.only(\\"does something really long and complicated so I have to write a very long name for the test\\", () => {
@@ -89,6 +101,18 @@ test(\`does something really long and complicated so I have to write a very long
   console.log(\\"hello!\\");
 });
 
+describe(\\"does something really long and complicated so I have to write a very long name for the describe block\\", () => {
+  it(\\"an example test\\", done => {
+    console.log(\\"hello!\\");
+  });
+});
+
+describe(\`does something really long and complicated so I have to write a very long name for the describe block\`, () => {
+  it(\`an example test\`, done => {
+    console.log(\\"hello!\\");
+  });
+});
+
 // Should break
 
 it.only(
@@ -129,7 +153,7 @@ it.only.only(
 "
 `;
 
-exports[`it.js 2`] = `
+exports[`test_declarations.js 2`] = `
 "// Shouldn't break
 
 it(\\"does something really long and complicated so I have to write a very long name for the test\\", () => {
@@ -163,6 +187,18 @@ test(\`does something really long and complicated so I have to write a very long
   console.log(\\"hello!\\");
 });
 
+describe(\\"does something really long and complicated so I have to write a very long name for the describe block\\", () => {
+  it(\\"an example test\\", (done) => {
+    console.log(\\"hello!\\");
+  });
+});
+
+describe(\`does something really long and complicated so I have to write a very long name for the describe block\`, () => {
+  it(\`an example test\`, (done) => {
+    console.log(\\"hello!\\");
+  });
+});
+
 // Should break
 
 it.only(\\"does something really long and complicated so I have to write a very long name for the test\\", () => {
@@ -218,6 +254,18 @@ test(\`does something really long and complicated so I have to write a very long
   console.log(\\"hello!\\");
 });
 
+describe(\\"does something really long and complicated so I have to write a very long name for the describe block\\", () => {
+  it(\\"an example test\\", done => {
+    console.log(\\"hello!\\");
+  });
+});
+
+describe(\`does something really long and complicated so I have to write a very long name for the describe block\`, () => {
+  it(\`an example test\`, done => {
+    console.log(\\"hello!\\");
+  });
+});
+
 // Should break
 
 it.only(

tests/test_declarations/test_declarations.js

@@ -31,6 +31,18 @@ test(`does something really long and complicated so I have to write a very long
   console.log("hello!");
 });
 
+describe("does something really long and complicated so I have to write a very long name for the describe block", () => {
+  it("an example test", (done) => {
+    console.log("hello!");
+  });
+});
+
+describe(`does something really long and complicated so I have to write a very long name for the describe block`, () => {
+  it(`an example test`, (done) => {
+    console.log("hello!");
+  });
+});
+
 // Should break
 
 it.only("does something really long and complicated so I have to write a very long name for the test", () => {