Fix printed schema descriptions that end with a double quote (")

src/utilities/__tests__/schemaPrinter-test.js

@@ -545,6 +545,60 @@ describe('Type System Printer', () => {
     `);
   });
 
+  it('One-line prints a short description', () => {
+    const description = 'This field is awesome';
+    const output = printSingleFieldSchema({
+      type: GraphQLString,
+      description,
+    });
+    expect(output).to.equal(dedent`
+      type Query {
+        """This field is awesome"""
+        singleField: String
+      }
+    `);
+    const recreatedRoot = buildSchema(output).getTypeMap()['Query'];
+    const recreatedField = recreatedRoot.getFields()['singleField'];
+    expect(recreatedField.description).to.equal(description);
+  });
+
+  it('Does not one-line print a description that ends with a quote', () => {
+    const description = 'This field is "awesome"';
+    const output = printSingleFieldSchema({
+      type: GraphQLString,
+      description,
+    });
+    expect(output).to.equal(dedent`
+      type Query {
+        """
+        This field is "awesome"
+        """
+        singleField: String
+      }
+    `);
+    const recreatedRoot = buildSchema(output).getTypeMap()['Query'];
+    const recreatedField = recreatedRoot.getFields()['singleField'];
+    expect(recreatedField.description).to.equal(description);
+  });
+
+  it('Preserves leading spaces when printing a description', () => {
+    const description = '    This field is "awesome"';
+    const output = printSingleFieldSchema({
+      type: GraphQLString,
+      description,
+    });
+    expect(output).to.equal(dedent`
+      type Query {
+        """    This field is "awesome"
+        """
+        singleField: String
+      }
+    `);
+    const recreatedRoot = buildSchema(output).getTypeMap()['Query'];
+    const recreatedField = recreatedRoot.getFields()['singleField'];
+    expect(recreatedField.description).to.equal(description);
+  });
+
   it('Print Introspection Schema', () => {
     const Query = new GraphQLObjectType({
       name: 'Query',
@@ -783,7 +837,30 @@ describe('Type System Printer', () => {
     `;
     expect(output).to.equal(introspectionSchema);
   });
-
+  it('Prints a field description that ends with a doublequote (")s', () => {
+    const description = 'This field is "awesome"';
+    const output = printSingleFieldSchema({
+      type: GraphQLString,
+      description,
+    });
+    expect(output).to.equal(dedent`
+      type Query {
+        """
+        This field is "awesome"
+        """
+        singleField: String
+      }
+    `);
+    const recreatedRoot = buildSchema(output).getTypeMap()['Query'];
+    const recreatedField = recreatedRoot.getFields()['singleField'];
+
+    /* Note: Additional space added to prevent parser from confusing trailing double
+     * quote inside description with the end of the block string. It shouldn't
+     * affect result since descriptions are interpreted as Markdown so trailing
+     * spaces are ignored.
+     */
+    expect(recreatedField.description).to.equal(description);
+  });
   it('Print Introspection Schema with comment descriptions', () => {
     const Query = new GraphQLObjectType({
       name: 'Query',

src/utilities/schemaPrinter.js

@@ -336,15 +336,30 @@ function printDescription(
     return printDescriptionWithComments(lines, indentation, firstInBlock);
   }
 
-  let description = indentation && !firstInBlock ? '\n' : '';
-  if (lines.length === 1 && lines[0].length < 70) {
-    description += indentation + '"""' + escapeQuote(lines[0]) + '"""\n';
-    return description;
+  let description =
+    indentation && !firstInBlock
+      ? '\n' + indentation + '"""'
+      : indentation + '"""';
+
+  // In some circumstances, a single line can be used for the description.
+  if (
+    lines.length === 1 &&
+    lines[0].length < 70 &&
+    lines[0][lines[0].length - 1] !== '"'
+  ) {
+    return description + escapeQuote(lines[0]) + '"""\n';
   }
 
-  description += indentation + '"""\n';
+  // Format a multi-line block quote to account for leading space.
+  const hasLeadingSpace = lines[0][0] === ' ' || lines[0][0] === '\t';
+  if (!hasLeadingSpace) {
+    description += '\n';
+  }
   for (let i = 0; i < lines.length; i++) {
-    description += indentation + escapeQuote(lines[i]) + '\n';
+    if (i !== 0 || !hasLeadingSpace) {
+      description += indentation;
+    }
+    description += escapeQuote(lines[i]) + '\n';
   }
   description += indentation + '"""\n';
   return description;