DelimiterCase / SnakeCase / ScreamingSnakeCase / KebabCase: Fix instantiations containing punctuations (#1080)

Author: som-sm

source/delimiter-case.d.ts

@@ -1,4 +1,4 @@
-import type {ApplyDefaultOptions} from './internal';
+import type {ApplyDefaultOptions, AsciiPunctuation, StartsWith} from './internal';
 import type {IsStringLiteral} from './is-literal';
 import type {Merge} from './merge';
 import type {DefaultWordsOptions, Words, WordsOptions} from './words';
@@ -16,7 +16,9 @@ type DelimiterCaseFromArray<
 	infer FirstWord extends string,
 	...infer RemainingWords extends string[],
 ]
-	? DelimiterCaseFromArray<RemainingWords, Delimiter, `${OutputString}${Delimiter}${FirstWord}`>
+	? DelimiterCaseFromArray<RemainingWords, Delimiter, `${OutputString}${
+		StartsWith<FirstWord, AsciiPunctuation> extends true ? '' : Delimiter
+	}${FirstWord}`>
 	: OutputString;
 
 type RemoveFirstLetter<S extends string> = S extends `${infer _}${infer Rest}`

source/internal/characters.d.ts

@@ -31,3 +31,37 @@ export type Whitespace =
 	| '\u{FEFF}';
 
 export type WordSeparators = '-' | '_' | Whitespace;
+
+export type AsciiPunctuation =
+	| '!'
+	| '"'
+	| '#'
+	| '$'
+	| '%'
+	| '&'
+	| '\''
+	| '('
+	| ')'
+	| '*'
+	| '+'
+	| ','
+	| '-'
+	| '.'
+	| '/'
+	| ':'
+	| ';'
+	| '<'
+	| '='
+	| '>'
+	| '?'
+	| '@'
+	| '['
+	| '\\'
+	| ']'
+	| '^'
+	| '_'
+	| '`'
+	| '{'
+	| '|'
+	| '}'
+	| '~';

test-d/delimiter-case.ts

@@ -112,6 +112,24 @@ expectType<'foo#bar' | 'bar#baz' | 'foo$bar' | 'bar$baz'>(unionValueAndDelimiter
 const stringPart: DelimiterCase<`foo${string}`, '#'> = 'fooSomeString';
 expectType<`foo${string}`>(stringPart);
 
+declare const withPunctuation: DelimiterCase<'onDialog:close', '#'>;
+expectType<'on#dialog:close'>(withPunctuation);
+
+declare const withPunctuation2: DelimiterCase<'foo-bar>>baz', '#'>;
+expectType<'foo#bar>>baz'>(withPunctuation2);
+
+declare const withPunctuation3: DelimiterCase<'card::after', '#'>;
+expectType<'card::after'>(withPunctuation3);
+
+declare const withPunctuation4: DelimiterCase<'div.card::after', '#'>;
+expectType<'div.card::after'>(withPunctuation4);
+
+declare const withPunctuationAndNumber: DelimiterCase<'foo-bar::01', '#'>;
+expectType<'foo#bar::01'>(withPunctuationAndNumber);
+
+declare const withPunctuationAndNumber2: DelimiterCase<'foo-bar::01', '#', {splitOnNumbers: true}>;
+expectType<'foo#bar::#01'>(withPunctuationAndNumber2);
+
 // Verifying example
 type OddCasedProperties<T> = {
 	[K in keyof T as DelimiterCase<K, '#'>]: T[K];

test-d/kebab-case.ts

@@ -78,3 +78,21 @@ expectType<'fo-o2bar'>(kebabFromNumberInTheMiddleNoSplitOnNumbersEdgeCase2);
 
 const kebabFromNumberInTheMiddleNoSplitOnNumbersEdgeCase3: KebabCase<'FOO22Bar'> = 'foo22-bar';
 expectType<'foo22-bar'>(kebabFromNumberInTheMiddleNoSplitOnNumbersEdgeCase3);
+
+declare const withPunctuation: KebabCase<'onDialog:close'>;
+expectType<'on-dialog:close'>(withPunctuation);
+
+declare const withPunctuation2: KebabCase<'foo-bar>>baz'>;
+expectType<'foo-bar>>baz'>(withPunctuation2);
+
+declare const withPunctuation3: KebabCase<'card::after'>;
+expectType<'card::after'>(withPunctuation3);
+
+declare const withPunctuation4: KebabCase<'div.card::after'>;
+expectType<'div.card::after'>(withPunctuation4);
+
+declare const withPunctuationAndNumber: KebabCase<'foo-bar::01'>;
+expectType<'foo-bar::01'>(withPunctuationAndNumber);
+
+declare const withPunctuationAndNumber2: KebabCase<'foo-bar::01', {splitOnNumbers: true}>;
+expectType<'foo-bar::-01'>(withPunctuationAndNumber2);

test-d/screaming-snake-case.ts

@@ -82,3 +82,21 @@ expectType<'FOO22_BAR'>(snakeFromNumberInTheMiddleNoSplitOnNumbersEdgeCase3);
 
 const nonStringFromNonString: ScreamingSnakeCase<[]> = [];
 expectType<[]>(nonStringFromNonString);
+
+declare const withPunctuation: ScreamingSnakeCase<'onDialog:close'>;
+expectType<'ON_DIALOG:CLOSE'>(withPunctuation);
+
+declare const withPunctuation2: ScreamingSnakeCase<'foo-bar>>baz'>;
+expectType<'FOO_BAR>>BAZ'>(withPunctuation2);
+
+declare const withPunctuation3: ScreamingSnakeCase<'card::after'>;
+expectType<'CARD::AFTER'>(withPunctuation3);
+
+declare const withPunctuation4: ScreamingSnakeCase<'div.card::after'>;
+expectType<'DIV.CARD::AFTER'>(withPunctuation4);
+
+declare const withPunctuationAndNumber: ScreamingSnakeCase<'foo-bar::01'>;
+expectType<'FOO_BAR::01'>(withPunctuationAndNumber);
+
+declare const withPunctuationAndNumber2: ScreamingSnakeCase<'foo-bar::01', {splitOnNumbers: true}>;
+expectType<'FOO_BAR::_01'>(withPunctuationAndNumber2);

test-d/snake-case.ts

@@ -81,3 +81,21 @@ expectType<'fo_o2bar'>(snakeFromNumberInTheMiddleNoSplitOnNumbersEdgeCase2);
 
 const snakeFromNumberInTheMiddleNoSplitOnNumbersEdgeCase3: SnakeCase<'FOO22Bar'> = 'foo22_bar';
 expectType<'foo22_bar'>(snakeFromNumberInTheMiddleNoSplitOnNumbersEdgeCase3);
+
+declare const withPunctuation: SnakeCase<'onDialog:close'>;
+expectType<'on_dialog:close'>(withPunctuation);
+
+declare const withPunctuation2: SnakeCase<'foo-bar>>baz'>;
+expectType<'foo_bar>>baz'>(withPunctuation2);
+
+declare const withPunctuation3: SnakeCase<'card::after'>;
+expectType<'card::after'>(withPunctuation3);
+
+declare const withPunctuation4: SnakeCase<'div.card::after'>;
+expectType<'div.card::after'>(withPunctuation4);
+
+declare const withPunctuationAndNumber: SnakeCase<'foo-bar::01'>;
+expectType<'foo_bar::01'>(withPunctuationAndNumber);
+
+declare const withPunctuationAndNumber2: SnakeCase<'foo-bar::01', {splitOnNumbers: true}>;
+expectType<'foo_bar::_01'>(withPunctuationAndNumber2);