feat(project): instantiate method for Boolean, String, Number, Null

Author: tjanc

packages/minim-api-description/lib/api-description.js

@@ -34,8 +34,10 @@ const copy = require('./elements/copy');
 const category = require('./elements/category');
 const extension = require('./elements/extension');
 const enumeration = require('./elements/enum');
+const defineInstantiate = require('./define-instantiate');
 
 const namespace = (options) => {
+  defineInstantiate(options.base);
   httpHeaders(options.base);
   hrefVariables(options.base);
   asset(options.base);

packages/minim-api-description/lib/define-instantiate.js

@@ -0,0 +1,120 @@
+/* eslint-disable no-bitwise, no-underscore-dangle */
+
+const setFlag = (mask, options) => (options | mask);
+const isFlag = (mask, options) => (options & mask) !== 0;
+
+const FIXED_FLAG = 1 << 0;
+const NULLABLE_FLAG = 1 << 1;
+
+function findDefault(e) {
+  if (undefined !== e._attributes) {
+    const result = e.attributes.get('default');
+    if (undefined !== result) {
+      return result;
+    }
+  }
+  return null;
+}
+
+function hasTypeAttribute(e, attribute) {
+  if (undefined !== e._attributes) {
+    const attrs = e.attributes.get('typeAttributes');
+    if (undefined !== attrs && undefined !== attrs.content) {
+      return undefined !== attrs.content.find(attr => attr.content === attribute);
+    }
+  }
+  return false;
+}
+
+const hasFixedTypeAttribute = e => hasTypeAttribute(e, 'fixed');
+const hasNullableTypeAttribute = e => hasTypeAttribute(e, 'nullable');
+
+function updateTypeAttributes(e, options) {
+  let result = options;
+  if (hasFixedTypeAttribute(e)) {
+    result = setFlag(FIXED_FLAG, result);
+  }
+  if (hasNullableTypeAttribute(e)) {
+    result = setFlag(NULLABLE_FLAG, result);
+  }
+  return result;
+}
+
+module.exports = (namespace) => {
+  const { Element } = namespace.elements;
+  const {
+    Array: ArrayElement,
+    String: StringElement,
+    Boolean: BooleanElement,
+    Number: NumberElement,
+    Null: NullElement,
+  } = namespace.elements;
+
+  function findFirstSample(e) {
+    if (undefined !== e._attributes) {
+      const samples = e.attributes.get('samples');
+      if (samples instanceof ArrayElement) {
+        if (undefined !== samples.content && samples.content.length > 0) {
+          return samples.content[0];
+        }
+      }
+    }
+    return null;
+  }
+
+  const isPrimitive = e => (e instanceof StringElement) || (e instanceof NumberElement) || (e instanceof BooleanElement);
+
+  // Generate default value for leaf elements (Boolean, String, Number, Null)
+  function generateValue(e) {
+    if (e instanceof BooleanElement) {
+      return false;
+    }
+    if (e instanceof NumberElement) {
+      return 0;
+    }
+    if (e instanceof StringElement) {
+      return '';
+    }
+    if (e instanceof NullElement) {
+      return null;
+    }
+    return undefined;
+  }
+
+  // Create instance of leaf element (Boolean, String, Number, Null)
+  function instantiateLeaf(e, options) {
+    const opts = updateTypeAttributes(e, options);
+    if (e.content) {
+      return [e.content, 'content'];
+    }
+    const sample = findFirstSample(e);
+    if (sample) {
+      return [sample.content, 'sample'];
+    }
+    const dflt = findDefault(e);
+    if (dflt) {
+      return [dflt.content, 'default'];
+    }
+    if (isFlag(NULLABLE_FLAG, opts)) {
+      return [null, 'content'];
+    }
+
+    return [generateValue(e), 'generated'];
+  }
+
+  function instantiate(e, options) {
+    if (isPrimitive(e) === true) {
+      return instantiateLeaf(e, options);
+    }
+    if (e instanceof NullElement) {
+      return instantiateLeaf(e, options);
+    }
+    return undefined;
+  }
+
+  if (!Object.getOwnPropertyNames(Element.prototype).includes('instantiate')) {
+    Object.defineProperty(Element.prototype, 'instantiate', {
+      value() { return instantiate(this, 0); },
+    });
+  }
+};

packages/minim-api-description/test/instantiate-test.js

@@ -0,0 +1,64 @@
+const { expect } = require('chai');
+const minim = require('minim');
+const apiDescription = require('../lib/api-description');
+
+const namespace = minim.namespace().use(apiDescription);
+
+const StringElement = namespace.elements.String;
+const ArrayElement = namespace.elements.Array;
+
+describe('instantiate StringElement', () => {
+  it('returns content', () => {
+    const element = new StringElement('hello');
+    const value = element.instantiate();
+
+    expect(value).to.deep.equal(['hello', 'content']);
+  });
+
+  it('prefers content over default and samples', () => {
+    const element = new StringElement('hello');
+    element.attributes.set('default', new StringElement('moin'));
+    element.attributes.set('samples', new ArrayElement(
+      new StringElement('zdravicko')
+    ));
+    const value = element.instantiate();
+
+    expect(value).to.deep.equal(['hello', 'content']);
+  });
+
+  it('prefers a sample over a default', () => {
+    const element = new StringElement();
+    element.attributes.set('default', new StringElement('moin'));
+    element.attributes.set('samples', new ArrayElement([
+      new StringElement('zdravicko'),
+    ]));
+    const value = element.instantiate();
+
+    expect(value).to.deep.equal(['zdravicko', 'sample']);
+  });
+
+  it('prefers default over generating a value', () => {
+    const element = new StringElement();
+    element.attributes.set('default', new StringElement('moin'));
+    const value = element.instantiate();
+
+    expect(value).to.deep.equal(['moin', 'default']);
+  });
+
+  it('generates an empty string if no content, default, samples and not nullable', () => {
+    const element = new StringElement();
+    const value = element.instantiate();
+
+    expect(value).to.deep.equal(['', 'generated']);
+  });
+
+  it('generates null if no content, default, samples and nullable', () => {
+    const element = new StringElement();
+    element.attributes.set('typeAttributes', new ArrayElement([
+      new StringElement('nullable'),
+    ]));
+    const value = element.instantiate();
+
+    expect(value).to.deep.equal([null, 'content']);
+  });
+});