diff --git a/src/cli/extract.ts b/src/cli/extract.ts
index d4c251f..16e91ab 100644
--- a/src/cli/extract.ts
+++ b/src/cli/extract.ts
@@ -1,53 +1,35 @@
 import {
   Node,
   ObjectExpression,
-  Property,
   ImportDeclaration,
   ImportSpecifier,
   CallExpression,
   Identifier,
+  Literal,
 } from 'estree'
 import delve from 'dlv'
 import { walk } from 'estree-walker'
 import { Ast } from 'svelte/types/compiler/interfaces'
 import { parse } from 'svelte/compiler'
 
+import { deepSet } from './includes/deepSet'
+import { getObjFromExpression } from './includes/getObjFromExpression'
+import { Message } from './types'
+
 const LIB_NAME = 'svelte-i18n'
 const DEFINE_MESSAGES_METHOD_NAME = 'defineMessages'
-const FORMAT_METHOD_NAMES = new Set(['format', '_'])
-
-interface Message {
-  node: Node
-  meta: {
-    id?: string
-    default?: string
-    [key: string]: any
-  }
-}
-
-const isNumberString = (n: string) => !Number.isNaN(parseInt(n))
-
-function deepSet(obj: any, path: string, value: any) {
-  const parts = path.replace(/\[(\w+)\]/gi, '.$1').split('.')
-  return parts.reduce((ref, part, i) => {
-    if (part in ref) return (ref = ref[part])
-
-    if (i < parts.length - 1) {
-      if (isNumberString(parts[i + 1])) {
-        return (ref = ref[part] = [])
-      }
-      return (ref = ref[part] = {})
-    }
-
-    return (ref[part] = value)
-  }, obj)
-}
+const FORMAT_METHOD_NAMES = new Set(['format', '_', 't'])
+const IGNORED_UTILITIES = new Set(['number', 'date', 'time'])
 
 function isFormatCall(node: Node, imports: Set<string>) {
   if (node.type !== 'CallExpression') return false
 
   let identifier: Identifier
-  if (node.callee.type === 'MemberExpression') {
+  if (
+    node.callee.type === 'MemberExpression' &&
+    node.callee.property.type === 'Identifier' &&
+    !IGNORED_UTILITIES.has(node.callee.property.name)
+  ) {
     identifier = node.callee.object as Identifier
   } else if (node.callee.type === 'Identifier') {
     identifier = node.callee
@@ -92,22 +74,6 @@ function getFormatSpecifiers(decl: ImportDeclaration) {
   ) as ImportSpecifier[]
 }
 
-function getObjFromExpression(exprNode: Node | ObjectExpression) {
-  if (exprNode.type !== 'ObjectExpression') return null
-  return exprNode.properties.reduce<Message>(
-    (acc, prop: Property) => {
-      // we only want primitives
-      if (prop.value.type !== 'Literal') return acc
-      if (prop.value.value !== Object(prop.value.value)) {
-        const key = (prop.key as Identifier).name as string
-        acc.meta[key] = prop.value.value
-      }
-      return acc
-    },
-    { node: exprNode, meta: {} }
-  )
-}
-
 export function collectFormatCalls(ast: Ast) {
   const importDecls = getLibImportDeclarations(ast)
 
@@ -122,14 +88,14 @@ export function collectFormatCalls(ast: Ast) {
   if (imports.size === 0) return []
 
   const calls: CallExpression[] = []
-  function formatCallsWalker(node: Node) {
+  function enter(node: Node) {
     if (isFormatCall(node, imports)) {
       calls.push(node as CallExpression)
       this.skip()
     }
   }
-  walk(ast.instance as any, { enter: formatCallsWalker })
-  walk(ast.html as any, { enter: formatCallsWalker })
+  walk(ast.instance as any, { enter })
+  walk(ast.html as any, { enter })
 
   return calls
 }
@@ -157,7 +123,9 @@ export function collectMessageDefinitions(ast: Ast) {
   })
 
   return definitions.flatMap(definitionDict =>
-    definitionDict.properties.map(propNode => propNode.value)
+    definitionDict.properties.map(
+      propNode => propNode.value as ObjectExpression
+    )
   )
 }
 
@@ -173,19 +141,18 @@ export function collectMessages(markup: string): Message[] {
         return getObjFromExpression(pathNode)
       }
 
-      if (pathNode.type !== 'Literal' || typeof pathNode.value !== 'string') {
-        return null
-      }
+      const node = pathNode as Literal
+      const id = node.value as string
 
       if (options && options.type === 'ObjectExpression') {
         const messageObj = getObjFromExpression(options)
-        messageObj.meta.id = pathNode.value
+        messageObj.meta.id = id
         return messageObj
       }
 
       return {
-        node: pathNode,
-        meta: { id: pathNode.value },
+        node,
+        meta: { id },
       }
     }),
   ].filter(Boolean)
diff --git a/src/cli/includes/deepSet.ts b/src/cli/includes/deepSet.ts
new file mode 100644
index 0000000..d4517e8
--- /dev/null
+++ b/src/cli/includes/deepSet.ts
@@ -0,0 +1,17 @@
+const isNumberString = (n: string) => !Number.isNaN(parseInt(n))
+
+export function deepSet(obj: any, path: string, value: any) {
+  const parts = path.replace(/\[(\w+)\]/gi, '.$1').split('.')
+  return parts.reduce((ref, part, i) => {
+    if (part in ref) return (ref = ref[part])
+
+    if (i < parts.length - 1) {
+      if (isNumberString(parts[i + 1])) {
+        return (ref = ref[part] = [])
+      }
+      return (ref = ref[part] = {})
+    }
+
+    return (ref[part] = value)
+  }, obj)
+}
diff --git a/src/cli/includes/getObjFromExpression.ts b/src/cli/includes/getObjFromExpression.ts
new file mode 100644
index 0000000..a992817
--- /dev/null
+++ b/src/cli/includes/getObjFromExpression.ts
@@ -0,0 +1,18 @@
+import { ObjectExpression, Property, Identifier } from 'estree'
+
+import { Message } from '../types'
+
+export function getObjFromExpression(exprNode: ObjectExpression) {
+  return exprNode.properties.reduce<Message>(
+    (acc, prop: Property) => {
+      if (prop.value.type !== 'Literal') return acc
+      // we only want primitives
+      if (prop.value.value !== Object(prop.value.value)) {
+        const key = (prop.key as Identifier).name as string
+        acc.meta[key] = prop.value.value
+      }
+      return acc
+    },
+    { node: exprNode, meta: {} }
+  )
+}
diff --git a/src/cli/types/index.ts b/src/cli/types/index.ts
new file mode 100644
index 0000000..9291827
--- /dev/null
+++ b/src/cli/types/index.ts
@@ -0,0 +1,10 @@
+import { Node } from 'estree'
+
+export interface Message {
+  node: Node
+  meta: {
+    id?: string
+    default?: string
+    [key: string]: any
+  }
+}
diff --git a/test/cli/extraction.test.ts b/test/cli/extract.test.ts
similarity index 64%
rename from test/cli/extraction.test.ts
rename to test/cli/extract.test.ts
index 77e192a..3f56577 100644
--- a/test/cli/extraction.test.ts
+++ b/test/cli/extract.test.ts
@@ -10,19 +10,33 @@ import {
 } from '../../src/cli/extract'
 
 describe('collecting format calls', () => {
-  it('should return nothing if there are no imports from the library', () => {
-    const ast = parse(`<script>const $_ = () => 0; $_();</script>`)
+  test('returns nothing if there are no imports', () => {
+    const ast = parse(`<script>
+      import Foo from 'foo';
+      const $_ = () => 0; $_();
+    </script>`)
     const calls = collectFormatCalls(ast)
     expect(calls).toHaveLength(0)
   })
 
-  it('should collect all format calls in the instance script', () => {
+  test('returns nothing if there are no format imports', () => {
+    const ast = parse(
+      `<script>
+        import { init } from 'svelte-i18n';
+        init({})
+      </script>`
+    )
+    const calls = collectFormatCalls(ast)
+    expect(calls).toHaveLength(0)
+  })
+
+  test('collects all format calls in the instance script', () => {
     const ast = parse(`<script>
     import { format, _ } from 'svelte-i18n'
-    $format('foo')
-    format('bar')
-    let label = $_({id:'bar'})
-    const a = { b: () => 0}
+      $format('foo')
+      format('bar')
+      let label = $_({id:'bar'})
+      const a = { b: () => 0}
     </script>`)
     const calls = collectFormatCalls(ast)
     expect(calls).toHaveLength(2)
@@ -30,24 +44,12 @@ describe('collecting format calls', () => {
     expect(calls[1]).toMatchObject({ type: 'CallExpression' })
   })
 
-  it('should collect all format calls with renamed imports', () => {
+  test('collects all format calls with renamed imports', () => {
     const ast = parse(`<script>
-    import { format as _x, _ as intl } from 'svelte-i18n'
-    $_x('foo')
-    $intl({ id: 'bar' })
-    </script>`)
-    const calls = collectFormatCalls(ast)
-    expect(calls).toHaveLength(2)
-    expect(calls[0]).toMatchObject({ type: 'CallExpression' })
-    expect(calls[1]).toMatchObject({ type: 'CallExpression' })
-  })
-
-  it('should collect all format utility calls', () => {
-    const ast = parse(`<script>
-    import { _ } from 'svelte-i18n'
-    $_.title('foo')
-    $_.capitalize({ id: 'bar' })
-    $_.number(10000)
+      import { format as _x, _ as intl, t as f } from 'svelte-i18n'
+      $_x('foo')
+      $intl({ id: 'bar' })
+      $f({ id: 'bar' })
     </script>`)
     const calls = collectFormatCalls(ast)
     expect(calls).toHaveLength(3)
@@ -55,24 +57,51 @@ describe('collecting format calls', () => {
     expect(calls[1]).toMatchObject({ type: 'CallExpression' })
     expect(calls[2]).toMatchObject({ type: 'CallExpression' })
   })
+
+  test('collects all string format utility calls', () => {
+    const ast = parse(`<script>
+      import { _ } from 'svelte-i18n'
+      $_.title('foo')
+      $_.capitalize({ id: 'bar' })
+      $_.lower({ id: 'bar' })
+      $_.upper({ id: 'bar' })
+    </script>`)
+    const calls = collectFormatCalls(ast)
+    expect(calls).toHaveLength(4)
+    expect(calls[0]).toMatchObject({ type: 'CallExpression' })
+    expect(calls[1]).toMatchObject({ type: 'CallExpression' })
+    expect(calls[2]).toMatchObject({ type: 'CallExpression' })
+    expect(calls[3]).toMatchObject({ type: 'CallExpression' })
+  })
+
+  test('ignores date, time and number calls', () => {
+    const ast = parse(`<script>
+      import { _ } from 'svelte-i18n'
+      $_.number(1000)
+      $_.date(new Date())
+      $_.time(new Date())
+    </script>`)
+    const calls = collectFormatCalls(ast)
+    expect(calls).toHaveLength(0)
+  })
 })
 
 describe('collecting message definitions', () => {
-  it('should return nothing if there are no imports from the library', () => {
+  test('returns nothing if there are no imports from the library', () => {
     const ast = parse(
       `<script>
-      import foo from 'foo';
-      import { dictionary } from 'svelte-i18n';
-      </script>`,
+        import foo from 'foo';
+        import { dictionary } from 'svelte-i18n';
+      </script>`
     )
     expect(collectMessageDefinitions(ast)).toHaveLength(0)
   })
 
-  it('should get all message definition objects', () => {
+  test('gets all message definition objects', () => {
     const ast = parse(`<script>
-    import { defineMessages } from 'svelte-i18n';
-    defineMessages({ foo: { id: 'foo' }, bar: { id: 'bar' } })
-    defineMessages({ baz: { id: 'baz' }, quix: { id: 'qux' } })
+      import { defineMessages } from 'svelte-i18n';
+      defineMessages({ foo: { id: 'foo' }, bar: { id: 'bar' } })
+      defineMessages({ baz: { id: 'baz' }, quix: { id: 'qux' } })
     </script>`)
     const definitions = collectMessageDefinitions(ast)
     expect(definitions).toHaveLength(4)
@@ -84,10 +113,11 @@ describe('collecting message definitions', () => {
 })
 
 describe('collecting messages', () => {
-  it('should collect all messages in both instance and html ASTs', () => {
+  test('collects all messages in both instance and html ASTs', () => {
     const markup = `
     <script>
       import { _, defineMessages } from 'svelte-i18n';
+
       console.log($_({ id: 'foo' }))
       console.log($_.title({ id: 'page.title' }))
 
@@ -96,10 +126,13 @@ describe('collecting messages', () => {
         disabled: { id: 'disabled', default:  'Disabled' }
       })
     </script>
+
     <div>{$_('msg_1')}</div>
     <div>{$_({id: 'msg_2'})}</div>
     <div>{$_('msg_3', { default: 'Message'})}</div>`
+
     const messages = collectMessages(markup)
+
     expect(messages).toHaveLength(7)
     expect(messages).toEqual(
       expect.arrayContaining([
@@ -114,15 +147,16 @@ describe('collecting messages', () => {
         expect.objectContaining({
           meta: { id: 'enabled', default: 'Enabled' },
         }),
-      ]),
+      ])
     )
   })
 })
 
 describe('messages extraction', () => {
-  it('should return a object built based on all found message paths', () => {
-    const markup = `
-    <script>import { _ } from 'svelte-i18n';</script>
+  test('returns a object built based on all found message paths', () => {
+    const markup = `<script>
+      import { _ } from 'svelte-i18n';
+    </script>
 
     <h1>{$_.title('title')}</h1>
     <h2>{$_({ id: 'subtitle'})}</h2>
@@ -131,16 +165,16 @@ describe('messages extraction', () => {
     expect(dict).toMatchObject({ title: '', subtitle: '' })
   })
 
-  it('creates deep nested properties', () => {
+  test('creates deep nested properties', () => {
     const markup = `
     <script>import { _ } from 'svelte-i18n';</script>
 
     <h1>{$_.title('home.page.title')}</h1>
     <h2>{$_({ id: 'home.page.subtitle'})}</h2>
     <ul>
-      <li>{$_('list[0]')}</li>
-      <li>{$_('list[1]')}</li>
-      <li>{$_('list[2]')}</li>
+      <li>{$_('list.0')}</li>
+      <li>{$_('list.1')}</li>
+      <li>{$_('list.2')}</li>
     </ul>
     `
     const dict = extractMessages(markup)
@@ -150,38 +184,38 @@ describe('messages extraction', () => {
     })
   })
 
-  it('creates a shallow dictionary', () => {
+  test('creates a shallow dictionary', () => {
     const markup = `
     <script>import { _ } from 'svelte-i18n';</script>
 
     <h1>{$_.title('home.page.title')}</h1>
     <h2>{$_({ id: 'home.page.subtitle'})}</h2>
     <ul>
-      <li>{$_('list[0]')}</li>
-      <li>{$_('list[1]')}</li>
-      <li>{$_('list[2]')}</li>
+      <li>{$_('list.0')}</li>
+      <li>{$_('list.1')}</li>
+      <li>{$_('list.2')}</li>
     </ul>
     `
     const dict = extractMessages(markup, { shallow: true })
     expect(dict).toMatchObject({
       'home.page.title': '',
       'home.page.subtitle': '',
-      'list[0]': '',
-      'list[1]': '',
-      'list[2]': '',
+      'list.0': '',
+      'list.1': '',
+      'list.2': '',
     })
   })
 
-  it('allow to pass a initial dictionary and only append non-existing props', () => {
+  test('allow to pass a initial dictionary and only append non-existing props', () => {
     const markup = `
     <script>import { _ } from 'svelte-i18n';</script>
 
     <h1>{$_.title('home.page.title')}</h1>
     <h2>{$_({ id: 'home.page.subtitle'})}</h2>
     <ul>
-      <li>{$_('list[0]')}</li>
-      <li>{$_('list[1]')}</li>
-      <li>{$_('list[2]')}</li>
+      <li>{$_('list.0')}</li>
+      <li>{$_('list.1')}</li>
+      <li>{$_('list.2')}</li>
     </ul>
     `
     const dict = extractMessages(markup, {
@@ -205,7 +239,7 @@ describe('messages extraction', () => {
     })
   })
 
-  it('allow to pass a initial dictionary and only append shallow non-existing props', () => {
+  test('allow to pass a initial dictionary and only append shallow non-existing props', () => {
     const markup = `
     <script>import { _ } from 'svelte-i18n';</script>