feat: Handle custom generators for faker

README.md

@@ -44,12 +44,13 @@ Changes the case of the enums. Accepts `upper-case#upperCase`, `pascal-case#pasc
 
 Allows you to define mappings for your custom scalars. Allows you to map any GraphQL Scalar to a
 [casual](https://github.com/boo1ean/casual#embedded-generators) embedded generator (string or
-function key) with optional arguments
+function key) with optional arguments, or a or [faker](https://fakerjs.dev/api/) generator with optional arguments
+
+Examples using **casual**
 
-Examples
 **With arguments**
 
-```
+```yaml
 plugins:
   - typescript-mock-data:
       scalars:
@@ -60,7 +61,7 @@ plugins:
 
 **With multiple arguments**
 
-```
+```yaml
 plugins:
   - typescript-mock-data:
       scalars:
@@ -73,13 +74,48 @@ plugins:
 
 **Shorthand if you don't have arguments**
 
-```
+```yaml
 plugins:
   - typescript-mock-data:
       scalars:
         Date: date # gets translated to casual.date()
 ```
 
+Examples using **faker**
+
+**With arguments**
+
+```yaml
+plugins:
+  - typescript-mock-data:
+      scalars:
+        Date: # gets translated to faker.date.past(10)
+          generator: date.past
+          arguments: 10
+```
+
+**With multiple arguments**
+
+```yaml
+plugins:
+  - typescript-mock-data:
+      scalars:
+        Description: # gets translated to faker.lorem.paragraphs(3, '\n')
+          generator: lorem.paragraphs
+          arguments:
+            - 3
+            - '\n'
+```
+
+**Shorthand if you don't have arguments**
+
+```yaml
+plugins:
+  - typescript-mock-data:
+      scalars:
+        Date: date.past # gets translated to faker.date.past()
+```
+
 **Custom value generator**
 
 ```yaml

src/index.ts

@@ -1,4 +1,5 @@
 import { ASTKindToNode, ListTypeNode, NamedTypeNode, parse, printSchema, TypeNode } from 'graphql';
+import { faker } from '@faker-js/faker';
 import casual from 'casual';
 import { PluginFunction, oldVisit } from '@graphql-codegen/plugin-helpers';
 import { pascalCase } from 'pascal-case';
@@ -101,7 +102,7 @@ const getScalarDefinition = (value: ScalarDefinition | ScalarGeneratorName): Sca
     return value;
 };
 
-const getCustomScalarValue = (customScalar: ScalarDefinition, opts: Options<NamedTypeNode>) => {
+const getCasualCustomScalarValue = (customScalar: ScalarDefinition, opts: Options<NamedTypeNode>) => {
     // If there is a mapping to a `casual` type, then use it and make sure
     // to call it if it's a function
     const embeddedGenerator = casual[customScalar.generator];
@@ -128,6 +129,60 @@ const getCustomScalarValue = (customScalar: ScalarDefinition, opts: Options<Name
     return value;
 };
 
+const getFakerGenerators = (generatorName: ScalarGeneratorName): [Function, string] => {
+    let embeddedGenerator: unknown = faker;
+    let dynamicGenerator = 'faker';
+
+    if (typeof generatorName === 'string') {
+        const generatorPath = generatorName.split('.');
+        for (const key of generatorPath) {
+            if (embeddedGenerator.hasOwnProperty(key)) {
+                embeddedGenerator = embeddedGenerator[key];
+                dynamicGenerator = `${dynamicGenerator}['${key}']`;
+            }
+        }
+    }
+
+    // If the faker generator is not a function, we can assume the path is wrong
+    if (typeof embeddedGenerator === 'function') {
+        return [embeddedGenerator, dynamicGenerator];
+    }
+
+    return [null, null];
+};
+
+const getFakerCustomScalarValue = (customScalar: ScalarDefinition, opts: Options<NamedTypeNode>) => {
+    // If there is a mapping to a `faker` type, then use it
+    const [embeddedGenerator, dynamicGenerator] = getFakerGenerators(customScalar.generator);
+    if (!embeddedGenerator && customScalar.generator) {
+        return customScalar.generator;
+    }
+
+    const generatorArgs: unknown[] = Array.isArray(customScalar.arguments)
+        ? customScalar.arguments
+        : [customScalar.arguments];
+    if (opts.dynamicValues) {
+        return `${dynamicGenerator}(...${JSON.stringify(generatorArgs)})`;
+    }
+    const value = embeddedGenerator(...generatorArgs);
+
+    if (typeof value === 'string') {
+        return `'${value}'`;
+    }
+    if (typeof value === 'object') {
+        return `${JSON.stringify(value)}`;
+    }
+    return value;
+};
+
+const getCustomScalarValue = (customScalar: ScalarDefinition, opts: Options<NamedTypeNode>) => {
+    if (opts.generateLibrary === 'casual') {
+        return getCasualCustomScalarValue(customScalar, opts);
+    }
+
+    return getFakerCustomScalarValue(customScalar, opts);
+};
+
 const getNamedType = (opts: Options<NamedTypeNode>): string | number | boolean => {
     if (!opts.currentType) {
         return '';

tests/scalars/__snapshots__/spec.ts.snap

@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`should generate custom scalars for native and custom types 1`] = `
+exports[`should generate custom scalars for native and custom types using casual 1`] = `
 "
 export const anA = (overrides?: Partial<A>): A => {
     return {
@@ -20,3 +20,24 @@ export const aB = (overrides?: Partial<B>): B => {
 };
 "
 `;
+
+exports[`should generate custom scalars for native and custom types using faker 1`] = `
+"
+export const anA = (overrides?: Partial<A>): A => {
+    return {
+        id: overrides && overrides.hasOwnProperty('id') ? overrides.id! : 83,
+        str: overrides && overrides.hasOwnProperty('str') ? overrides.str! : 'Corrupti qui incidunt eius consequatur qui.',
+        obj: overrides && overrides.hasOwnProperty('obj') ? overrides.obj! : aB(),
+        anyObject: overrides && overrides.hasOwnProperty('anyObject') ? overrides.anyObject! : '[email protected]',
+    };
+};
+
+export const aB = (overrides?: Partial<B>): B => {
+    return {
+        int: overrides && overrides.hasOwnProperty('int') ? overrides.int! : -93,
+        flt: overrides && overrides.hasOwnProperty('flt') ? overrides.flt! : -24.51,
+        bool: overrides && overrides.hasOwnProperty('bool') ? overrides.bool! : false,
+    };
+};
+"
+`;

tests/scalars/spec.ts

@@ -1,7 +1,7 @@
 import { plugin } from '../../src';
 import testSchema from './schema';
 
-it('should generate custom scalars for native and custom types', async () => {
+it('should generate custom scalars for native and custom types using casual', async () => {
     const result = await plugin(testSchema, [], {
         scalars: {
             String: 'string',
@@ -45,3 +45,49 @@ it('should generate custom scalars for native and custom types', async () => {
 
     expect(result).toMatchSnapshot();
 });
+
+it('should generate custom scalars for native and custom types using faker', async () => {
+    const result = await plugin(testSchema, [], {
+        generateLibrary: 'faker',
+        scalars: {
+            String: 'lorem.sentence',
+            Float: {
+                generator: 'datatype.float',
+                arguments: [{ min: -100, max: 0}],
+            },
+            ID: {
+                generator: 'datatype.number',
+                arguments: [{ min: 1, max: 100}],
+            },
+            Boolean: 'false',
+            Int: {
+                generator: 'datatype.number',
+                arguments: [{ min: -100, max: 0}],
+            },
+            AnyObject: 'internet.email',
+        },
+    });
+
+    expect(result).toBeDefined();
+
+    // String
+    expect(result).toContain(
+        "str: overrides && overrides.hasOwnProperty('str') ? overrides.str! : 'Corrupti qui incidunt eius consequatur qui.',",
+    );
+
+    // Float
+    expect(result).toContain(
+        "flt: overrides && overrides.hasOwnProperty('flt') ? overrides.flt! : -24.51,",
+    );
+
+    // ID
+    expect(result).toContain("id: overrides && overrides.hasOwnProperty('id') ? overrides.id! : 83,");
+
+    // Boolean
+    expect(result).toContain("bool: overrides && overrides.hasOwnProperty('bool') ? overrides.bool! : false");
+
+    // Int
+    expect(result).toContain("int: overrides && overrides.hasOwnProperty('int') ? overrides.int! : -93,");
+
+    expect(result).toMatchSnapshot();
+});