Add test and support for deprecated args

Author: smitt04

src/type/definition.js

@@ -743,6 +743,8 @@ function defineFieldMap<TSource, TContext>(
           description: arg.description === undefined ? null : arg.description,
           type: arg.type,
           defaultValue: arg.defaultValue,
+          isDeprecated: Boolean(arg.deprecationReason),
+          deprecationReason: arg.deprecationReason,
           astNode: arg.astNode,
         };
       });

src/utilities/__tests__/buildASTSchema-test.js

@@ -631,6 +631,8 @@ describe('Schema Builder', () => {
         field1: String @deprecated
         field2: Int @deprecated(reason: "Because I said so")
         enum: MyEnum
+        field3(oldArg: String @deprecated, arg: String): String
+        field4(oldArg: String @deprecated(reason: "why not?"), arg: String): String
       }
     `;
     const output = cycleOutput(body);
@@ -658,6 +660,14 @@ describe('Schema Builder', () => {
 
     expect(rootFields.field2.isDeprecated).to.equal(true);
     expect(rootFields.field2.deprecationReason).to.equal('Because I said so');
+
+    const field3OldArg = rootFields.field3.args[0];
+    expect(field3OldArg.isDeprecated).to.equal(true);
+    expect(field3OldArg.deprecationReason).to.equal('No longer supported');
+
+    const field4OldArg = rootFields.field4.args[0];
+    expect(field4OldArg.isDeprecated).to.equal(true);
+    expect(field4OldArg.deprecationReason).to.equal('why not?');
   });
 
   it('Correctly assign AST nodes', () => {

src/utilities/buildASTSchema.js

@@ -309,6 +309,7 @@ export class ASTDefinitionBuilder {
       type,
       description: getDescription(value, this._options),
       defaultValue: valueFromAST(value.defaultValue, type),
+      deprecationReason: getDeprecationReason(value),
       astNode: value,
     };
   }

src/utilities/schemaPrinter.js

@@ -300,7 +300,7 @@ function printInputValue(arg) {
   if (!isInvalid(arg.defaultValue)) {
     argDecl += ` = ${print(astFromValue(arg.defaultValue, arg.type))}`;
   }
-  return argDecl;
+  return argDecl + printDeprecated(arg);
 }
 
 function printDirective(directive, options) {