Skip to content

[stdlib] default separator for joining strings (SE-0133) #3838

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Jul 29, 2016
Merged

[stdlib] default separator for joining strings (SE-0133) #3838

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 2 additions & 2 deletions stdlib/public/core/String.swift
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -767,9 +767,9 @@ extension Sequence where Iterator.Element == String {
/// // Prints "Vivien, Marlon, Kim, Karl"
///
/// - Parameter separator: A string to insert between each of the elements
/// in this sequence.
/// in this sequence. The default separator is an empty string.
/// - Returns: A single, concatenated string.
public func joined(separator: String) -> String {
public func joined(separator: String = "") -> String {
var result = ""

// FIXME(performance): this code assumes UTF-16 in-memory representation.
Expand Down
2 changes: 1 addition & 1 deletion test/IDE/print_type_interface.swift
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -83,4 +83,4 @@ extension D {
// TYPE5-DAG: public func split(separator: String, maxSplits: Int = default, omittingEmptySubsequences: Bool = default) -> [ArraySlice<String>]
// TYPE5-DAG: public func formIndex(_ i: inout Int, offsetBy n: Int)
// TYPE5-DAG: public func distance(from start: Int, to end: Int) -> Int
// TYPE5-DAG: public func joined(separator: String) -> String
// TYPE5-DAG: public func joined(separator: String = default) -> String
70 changes: 33 additions & 37 deletions validation-test/stdlib/Join.swift.gyb
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -277,7 +277,7 @@ collections += [(array, 'RandomAccess') for array in other_array_types]
% label = ''
% end

JoinTestSuite.test("${Base}.join()") {
JoinTestSuite.test("${Base}.joined(separator:)") {
for test in joinWithSeparatorTests {
let elements = ${Base}(${label} test.elements.map {
${Base}(${label} $0)
Expand All @@ -288,7 +288,7 @@ JoinTestSuite.test("${Base}.join()") {
}
}

JoinTestSuite.test("${Base}.join()/_copyToContiguousArray()") {
JoinTestSuite.test("${Base}.joined(separator:)/_copyToContiguousArray()") {
for test in joinWithSeparatorTests {
let elements = ${Base}(${label} test.elements.map {
${Base}(${label} $0)
Expand All @@ -301,47 +301,43 @@ JoinTestSuite.test("${Base}.join()/_copyToContiguousArray()") {

% end

func join(_ separator: String, _ elements: [String]) -> String {
return elements.joined(separator: separator)
}

JoinTestSuite.test("String.joined(separator:)") {
//
// Test the free function.
//
JoinTestSuite.test("Sequence<String>.joined(separator:)") {
// Default separator (empty).
expectEqual("", [].joined())
expectEqual("", [""].joined())
expectEqual("", ["", ""].joined())
expectEqual("", ["", "", ""].joined())
expectEqual("a", ["a"].joined())
expectEqual("ab", ["a", "b"].joined())
expectEqual("abc", ["a", "b", "c"].joined())
expectEqual("abcdef", ["ab", "cd", "ef"].joined())

// Empty separator.
expectEqual("", join("", []))
expectEqual("", join("", [""]))
expectEqual("", join("", ["", ""]))
expectEqual("", join("", ["", "", ""]))
expectEqual("a", join("", ["a"]))
expectEqual("ab", join("", ["a", "b"]))
expectEqual("abc", join("", ["a", "b", "c"]))
expectEqual("abcdef", join("", ["ab", "cd", "ef"]))
expectEqual("", [].joined(separator: ""))
expectEqual("", [""].joined(separator: ""))
expectEqual("", ["", ""].joined(separator: ""))
expectEqual("", ["", "", ""].joined(separator: ""))
expectEqual("a", ["a"].joined(separator: ""))
expectEqual("ab", ["a", "b"].joined(separator: ""))
expectEqual("abc", ["a", "b", "c"].joined(separator: ""))
expectEqual("abcdef", ["ab", "cd", "ef"].joined(separator: ""))

// 1-element separator.
expectEqual("", join("x", [""]))
expectEqual("x", join("x", ["", ""]))
expectEqual("xx", join("x", ["", "", ""]))
expectEqual("a", join("x", ["a"]))
expectEqual("axb", join("x", ["a", "b"]))
expectEqual("axbxc", join("x", ["a", "b", "c"]))
expectEqual("abxcdxef", join("x", ["ab", "cd", "ef"]))
expectEqual("", [""].joined(separator: "x"))
expectEqual("x", ["", ""].joined(separator: "x"))
expectEqual("xx", ["", "", ""].joined(separator: "x"))
expectEqual("a", ["a"].joined(separator: "x"))
expectEqual("axb", ["a", "b"].joined(separator: "x"))
expectEqual("axbxc", ["a", "b", "c"].joined(separator: "x"))
expectEqual("abxcdxef", ["ab", "cd", "ef"].joined(separator: "x"))

// 2-element separator.
expectEqual("", join("xy", [""]))
expectEqual("xy", join("xy", ["", ""]))
expectEqual("xyxy", join("xy", ["", "", ""]))
expectEqual("a", join("xy", ["a"]))
expectEqual("axyb", join("xy", ["a", "b"]))
expectEqual("axybxyc", join("xy", ["a", "b", "c"]))
expectEqual("abxycdxyef", join("xy", ["ab", "cd", "ef"]))

//
// Test forwarding instance function.
//

expectEqual("", [""].joined(separator: "xy"))
expectEqual("xy", ["", ""].joined(separator: "xy"))
expectEqual("xyxy", ["", "", ""].joined(separator: "xy"))
expectEqual("a", ["a"].joined(separator: "xy"))
expectEqual("axyb", ["a", "b"].joined(separator: "xy"))
expectEqual("axybxyc", ["a", "b", "c"].joined(separator: "xy"))
expectEqual("abxycdxyef", ["ab", "cd", "ef"].joined(separator: "xy"))
}

Expand Down