Basename / Dirname filters

CHANGELOG.md

@@ -14,7 +14,9 @@ _None_
 
 ### New Features
 
-_None_
+* Added the `basename` and `dirname` string filters for getting a filename, or parent folder (respectively), out of a path.  
+  [David Jennes](https://github.com/djbe) 
+  [#60](https://github.com/SwiftGen/StencilSwiftKit/pull/60)
 
 ### Internal Changes
 

Documentation/filters-strings.md

@@ -2,6 +2,16 @@
 
 This is a list of filters that are added by StencilSwiftKit on top of the filters already provided by Stencil (which you can [find here](http://stencil.fuller.li/en/latest/builtins.html#built-in-filters)).
 
+## Filter: `basename`
+
+Get the last component of a path, essentially the filename (and extension).
+
+| Input                  | Output         |
+|------------------------|----------------|
+| `test.jpg`             | `test.jpg`     |
+| `some/folder/test.jpg` | `test.jpg`     |
+| `file.txt.png`         | `file.txt.png` |
+
 ## Filter: `camelToSnakeCase`
 
 Transforms text from camelCase to snake_case.
@@ -25,6 +35,25 @@ By default it converts to lower case, unless a single optional argument is set t
 | `URLChooser`             | `URL_Chooser`            |
 | `PLEASE_STOP_SCREAMING!` | `PLEASE_STOP_SCREAMING!` |
 
+## Filter: `contains`
+
+Checks if the string contains given substring - works the same as Swift's `String.contains`.
+
+| Input             | Output          |
+|-------------------|-----------------|
+| `Hello` `el`      | true            |
+| `Hi mates!` `yo`  | false           |
+
+## Filter: `dirname`
+
+Remove the last component of a path, essentially returning the path without the filename (and extension).
+
+| Input                  | Output        |
+|------------------------|---------------|
+| `test.jpg`             | ``            |
+| `some/folder/test.jpg` | `some/folder` |
+| `file.txt.png`         | ``            |
+
 ## Filter: `escapeReservedKeywords`
 
 Checks if the given string matches a reserved Swift keyword. If it does, wrap the string in escape characters (backticks).
@@ -35,6 +64,34 @@ Checks if the given string matches a reserved Swift keyword. If it does, wrap th
 | `self`  | `` `self` `` |
 | `Any`   | `` `Any` ``  |
 
+## Filter: `hasPrefix`
+
+Checks if the string has the given prefix - works the same as Swift's `String.hasPrefix`.
+
+| Input             | Output          |
+|-------------------|-----------------|
+| `Hello` `Hi`      | false           |
+| `Hi mates!` `H`   | true            |
+
+## Filter: `hasSuffix`
+
+Checks if the string has the given suffix - works the same as Swift's `String.hasSuffix`.
+
+| Input             | Output          |
+|-------------------|-----------------|
+| `Hello` `llo`     | true            |
+| `Hi mates!` `?`   | false           |
+
+## Filter: `lowerFirstLetter`
+
+Simply lowercases the first character, leaving the other characters untouched.
+
+| Input           | Output          |
+|-----------------|-----------------|
+| `Hello`         | `hello`         |
+| `PeopleChooser` | `peopleChooser` |
+| `Hi There!`     | `hi There!`     |
+
 ## Filter: `lowerFirstWord`
 
 Transforms an arbitrary string so that only the first "word" is lowercased.
@@ -71,6 +128,16 @@ This filter has a couple of modes that you can specifiy using an optional argume
 | `test, \ntest, \ntest` | `test, test, test`    |
 | ` test test `          | `test test`           |
 
+## Filter: `replace`
+
+Replaces the given substring with the given replacement in the source string.
+Works the same as Swift's `String.replacingOccurrences`.
+
+| Input             | Output          |
+|-------------------|-----------------|
+| `Hello` `l` `k`   | `Hekko`         |
+| `Europe` `e` `a`  | `Europa`        |
+
 ## Filter: `snakeToCamelCase`
 
 Transforms a string in "snake_case" format into one in "camelCase" format, following the steps below:
@@ -128,50 +195,3 @@ Note that even if very similar, this filter differs from the `capitalized` filte
 |-----------------|-----------------|
 | `hello`         | `Hello`         |
 | `peopleChooser` | `PeopleChooser` |
-
-## Filter: `lowerFirstLetter`
-
-Simply lowercases the first character, leaving the other characters untouched.
-
-| Input           | Output          |
-|-----------------|-----------------|
-| `Hello`         | `hello`         |
-| `PeopleChooser` | `peopleChooser` |
-| `Hi There!`     | `hi There!`     |
-
-## Filter: `contains`
-
-Checks if the string contains given substring - works the same as Swift's `String.contains`.
-
-| Input             | Output          |
-|-------------------|-----------------|
-| `Hello` `el`      | true            |
-| `Hi mates!` `yo`  | false           |
-
-## Filter: `hasPrefix`
-
-Checks if the string has the given prefix - works the same as Swift's `String.hasPrefix`.
-
-| Input             | Output          |
-|-------------------|-----------------|
-| `Hello` `Hi`      | false           |
-| `Hi mates!` `H`   | true            |
-
-## Filter: `hasSuffix`
-
-Checks if the string has the given suffix - works the same as Swift's `String.hasSuffix`.
-
-| Input             | Output          |
-|-------------------|-----------------|
-| `Hello` `llo`     | true            |
-| `Hi mates!` `?`   | false           |
-
-## Filter: `replace`
-
-Replaces the given substring with the given replacement in the source string.
-Works the same as Swift's `String.replacingOccurrences`.
-
-| Input             | Output          |
-|-------------------|-----------------|
-| `Hello` `l` `k`   | `Hekko`         |
-| `Europe` `e` `a`  | `Europa`        |

README.md

@@ -25,13 +25,19 @@
 ## Filters
 
 * [String filters](Documentation/filters-strings.md):
+  * `basename`: Get the filename from a path.
   * `camelToSnakeCase`: Transforms text from camelCase to snake_case. By default it converts to lower case, unless a single optional argument is set to "false", "no" or "0".
+  * `contains`: Check if a string contains a specific substring.
+  * `dirname`: Get the path to the parent folder from a path.
   * `escapeReservedKeywords`: Escape keywords reserved in the Swift language, by wrapping them inside backticks so that the can be used as regular escape keywords in Swift code.
+  * `hasPrefix` / `hasSuffix`: Check if a string starts/ends with a specific substring.
+  * `lowerFirstLetter`: Lowercases only the first letter of a string.
   * `lowerFirstWord`: Lowercases only the first word of a string.
   * `removeNewlines`: Removes newlines and other whitespace characters, depending on the mode ("all" or "leading").
+  * `replace`: Replaces instances of a substring with a new string.
   * `snakeToCamelCase`: Transforms text from snake_case to camelCase. By default it keeps leading underscores, unless a single optional argument is set to "true", "yes" or "1".
   * `swiftIdentifier`: Transforms an arbitrary string into a valid Swift identifier (using only valid characters for a Swift identifier as defined in the Swift language reference)
-  * `titlecase`: Uppercases only the first character
+  * `upperFirstLetter`: Uppercases only the first character
 * [Number filters](Documentation/filters-numbers.md):
   * `int255toFloat`
   * `hexToInt`

Sources/Environment.swift

@@ -13,19 +13,21 @@ public extension Extension {
     registerTag("call", parser: CallNode.parse)
     registerTag("map", parser: MapNode.parse)
 
+    registerFilter("basename", filter: Filters.Strings.basename)
     registerFilter("camelToSnakeCase", filter: Filters.Strings.camelToSnakeCase)
+    registerFilter("contains", filter: Filters.Strings.contains)
+    registerFilter("dirname", filter: Filters.Strings.dirname)
     registerFilter("escapeReservedKeywords", filter: Filters.Strings.escapeReservedKeywords)
+    registerFilter("hasPrefix", filter: Filters.Strings.hasPrefix)
+    registerFilter("hasSuffix", filter: Filters.Strings.hasSuffix)
+    registerFilter("lowerFirstLetter", filter: Filters.Strings.lowerFirstLetter)
     registerFilter("lowerFirstWord", filter: Filters.Strings.lowerFirstWord)
     registerFilter("removeNewlines", filter: Filters.Strings.removeNewlines)
+    registerFilter("replace", filter: Filters.Strings.replace)
     registerFilter("snakeToCamelCase", filter: Filters.Strings.snakeToCamelCase)
     registerFilter("swiftIdentifier", filter: Filters.Strings.swiftIdentifier)
     registerFilter("titlecase", filter: Filters.Strings.upperFirstLetter)
     registerFilter("upperFirstLetter", filter: Filters.Strings.upperFirstLetter)
-    registerFilter("lowerFirstLetter", filter: Filters.Strings.lowerFirstLetter)
-    registerFilter("contains", filter: Filters.Strings.contains)
-    registerFilter("hasPrefix", filter: Filters.Strings.hasPrefix)
-    registerFilter("hasSuffix", filter: Filters.Strings.hasSuffix)
-    registerFilter("replace", filter: Filters.Strings.replace)
 
     registerFilter("hexToInt", filter: Filters.Numbers.hexToInt)
     registerFilter("int255toFloat", filter: Filters.Numbers.int255toFloat)

Sources/Filters+Strings.swift

@@ -226,6 +226,26 @@ extension Filters {
       return string.hasSuffix(suffix)
     }
 
+    /// Converts a file path to just the filename, stripping any path components before it.
+    ///
+    /// - Parameter value: the value to be processed
+    /// - Returns: the basename of the path
+    /// - Throws: FilterError.invalidInputType if the value parameter isn't a string
+    static func basename(_ value: Any?) throws -> Any? {
+      guard let string = value as? String else { throw Filters.Error.invalidInputType }
+      return (string as NSString).lastPathComponent
+    }
+
+    /// Converts a file path to just the path without the filename.
+    ///
+    /// - Parameter value: the value to be processed
+    /// - Returns: the dirname of the path
+    /// - Throws: FilterError.invalidInputType if the value parameter isn't a string
+    static func dirname(_ value: Any?) throws -> Any? {
+      guard let string = value as? String else { throw Filters.Error.invalidInputType }
+      return (string as NSString).deletingLastPathComponent
+    }
+
     // MARK: - Private methods
 
     private static func removeLeadingWhitespaces(from string: String) -> String {

Tests/StencilSwiftKitTests/StringFiltersTests.swift

@@ -467,3 +467,38 @@ extension StringFiltersTests {
     }
   }
 }
+
+extension StringFiltersTests {
+  func testBasename() throws {
+    let expectations = [
+      "/tmp/scratch.tiff": "scratch.tiff",
+      "/tmp/scratch": "scratch",
+      "/tmp/": "tmp",
+      "scratch///": "scratch",
+      "/": "/"
+    ]
+
+    for (input, expected) in expectations {
+      let result = try Filters.Strings.basename(input) as? String
+      XCTAssertEqual(result, expected)
+    }
+  }
+}
+
+extension StringFiltersTests {
+  func testDirname() throws {
+    let expectations = [
+      "/tmp/scratch.tiff": "/tmp",
+      "/tmp/lock/": "/tmp",
+      "/tmp/": "/",
+      "/tmp": "/",
+      "/": "/",
+      "scratch.tiff": ""
+    ]
+
+    for (input, expected) in expectations {
+      let result = try Filters.Strings.dirname(input) as? String
+      XCTAssertEqual(result, expected)
+    }
+  }
+}