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[typescript] union types incorrectly indented after comments

See original GitHub issue

Prettier 1.16.4 Playground link

--parser typescript

Input:

export type TransformedSource = {
  code: string;
  map?:
    // copied from https://github.com/DefinitelyTyped/DefinitelyTyped/blob/363cdf403a74e0372e87bbcd15eb1668f4c5230b/types/babel__core/index.d.ts#L371-L379
    | {
        version: number;
        sources: string[];
        names: string[];
        sourceRoot?: string;
        sourcesContent?: string[];
        mappings: string;
        file: string;
      }
    | string
    | null;
};

export type TransformedSource = {
  code: string,
  map?: // copied from https://github.com/DefinitelyTyped/DefinitelyTyped/blob/363cdf403a74e0372e87bbcd15eb1668f4c5230b/types/babel__core/index.d.ts#L371-L379
  | {
        version: number,
        sources: string[],
        names: string[],
        sourceRoot?: string,
        sourcesContent?: string[],
        mappings: string,
        file: string
      }
    | string
    | null
};

Output:

export type TransformedSource = {
  code: string;
  map?: // copied from https://github.com/DefinitelyTyped/DefinitelyTyped/blob/363cdf403a74e0372e87bbcd15eb1668f4c5230b/types/babel__core/index.d.ts#L371-L379

    | {
        version: number;
        sources: string[];
        names: string[];
        sourceRoot?: string;
        sourcesContent?: string[];
        mappings: string;
        file: string;
      }
    | string
    | null;
};

export type TransformedSource = {
  code: string;
  map?:  // copied from https://github.com/DefinitelyTyped/DefinitelyTyped/blob/363cdf403a74e0372e87bbcd15eb1668f4c5230b/types/babel__core/index.d.ts#L371-L379
    | {
        version: number;
        sources: string[];
        names: string[];
        sourceRoot?: string;
        sourcesContent?: string[];
        mappings: string;
        file: string;
      }
    | string
    | null;
};

Second Output:

export type TransformedSource = {
  code: string;
  map?:  // copied from https://github.com/DefinitelyTyped/DefinitelyTyped/blob/363cdf403a74e0372e87bbcd15eb1668f4c5230b/types/babel__core/index.d.ts#L371-L379
    | {
        version: number;
        sources: string[];
        names: string[];
        sourceRoot?: string;
        sourcesContent?: string[];
        mappings: string;
        file: string;
      }
    | string
    | null;
};

export type TransformedSource = {
  code: string;
  map?:  // copied from https://github.com/DefinitelyTyped/DefinitelyTyped/blob/363cdf403a74e0372e87bbcd15eb1668f4c5230b/types/babel__core/index.d.ts#L371-L379
    | {
        version: number;
        sources: string[];
        names: string[];
        sourceRoot?: string;
        sourcesContent?: string[];
        mappings: string;
        file: string;
      }
    | string
    | null;
};

Expected behavior: For the output to become the second result after a single prettier run. This happens using babylon and flow parser as well.

Issue Analytics

State:
Created 5 years ago
Comments:5 (4 by maintainers)

Top GitHub Comments

1reaction

SimenBcommented, Feb 11, 2019

Yeah, that’s what happens on the second run, in addition to a deletion of a blank line.

Maybe simpler to see:

Start:

export type TransformedSource = {
  code: string;
  map?:

  // copied from https://github.com/DefinitelyTyped/DefinitelyTyped/blob/363cdf403a74e0372e87bbcd15eb1668f4c5230b/types/babel__core/index.d.ts#L371-L379
    | {
        version: number;
        sources: string[];
        names: string[];
        sourceRoot?: string;
        sourcesContent?: string[];
        mappings: string;
        file: string;
      }
    | string
    | null;
};

Diff after running prettier once:

@@ -1,8 +1,7 @@
 export type TransformedSource = {
   code: string;
-  map?:
+  map?: // copied from https://github.com/DefinitelyTyped/DefinitelyTyped/blob/363cdf403a74e0372e87bbcd15eb1668f4c5230b/types/babel__core/index.d.ts#L371-L379
 
-  // copied from https://github.com/DefinitelyTyped/DefinitelyTyped/blob/363cdf403a74e0372e87bbcd15eb1668f4c5230b/types/babel__core/index.d.ts#L371-L379
     | {
         version: number;
         sources: string[];

Diff after running prettier twice:

@@ -1,8 +1,6 @@
 export type TransformedSource = {
   code: string;
-  map?:
-
-  // copied from https://github.com/DefinitelyTyped/DefinitelyTyped/blob/363cdf403a74e0372e87bbcd15eb1668f4c5230b/types/babel__core/index.d.ts#L371-L379
+  map?:  // copied from https://github.com/DefinitelyTyped/DefinitelyTyped/blob/363cdf403a74e0372e87bbcd15eb1668f4c5230b/types/babel__core/index.d.ts#L371-L379
     | {
         version: number;
         sources: string[];

Diff between first and second run of prettier:

@@ -1,7 +1,6 @@
 export type TransformedSource = {
   code: string;
-  map?: // copied from https://github.com/DefinitelyTyped/DefinitelyTyped/blob/363cdf403a74e0372e87bbcd15eb1668f4c5230b/types/babel__core/index.d.ts#L371-L379
-
+  map?:  // copied from https://github.com/DefinitelyTyped/DefinitelyTyped/blob/363cdf403a74e0372e87bbcd15eb1668f4c5230b/types/babel__core/index.d.ts#L371-L379
     | {
         version: number;
         sources: string[];

0reactions

thorn0commented, May 7, 2020

The idempotence issue is gone, but the indentation after the comment is off:

Prettier 2.0.5 Playground link

--arrow-parens avoid
--parser typescript
--trailing-comma none

Input:

export type TransformedSource = {
  code: string;
  map?:
    // copied from https://github.com/DefinitelyTyped/DefinitelyTyped/blob/363cdf403a74e0372e87bbcd15eb1668f4c5230b/types/babel__core/index.d.ts#L371-L379
    | {
        version: number;
        sources: string[];
        names: string[];
        sourceRoot?: string;
        sourcesContent?: string[];
        mappings: string;
        file: string;
      }
    | string
    | null;
};

export type TransformedSource = {
  code: string,
  map?: // copied from https://github.com/DefinitelyTyped/DefinitelyTyped/blob/363cdf403a74e0372e87bbcd15eb1668f4c5230b/types/babel__core/index.d.ts#L371-L379
  | {
        version: number,
        sources: string[],
        names: string[],
        sourceRoot?: string,
        sourcesContent?: string[],
        mappings: string,
        file: string
      }
    | string
    | null
};

Output:

export type TransformedSource = {
  code: string;
  map?: // copied from https://github.com/DefinitelyTyped/DefinitelyTyped/blob/363cdf403a74e0372e87bbcd15eb1668f4c5230b/types/babel__core/index.d.ts#L371-L379
  | {
        version: number;
        sources: string[];
        names: string[];
        sourceRoot?: string;
        sourcesContent?: string[];
        mappings: string;
        file: string;
      }
    | string
    | null;
};

export type TransformedSource = {
  code: string;
  map?: // copied from https://github.com/DefinitelyTyped/DefinitelyTyped/blob/363cdf403a74e0372e87bbcd15eb1668f4c5230b/types/babel__core/index.d.ts#L371-L379
  | {
        version: number;
        sources: string[];
        names: string[];
        sourceRoot?: string;
        sourcesContent?: string[];
        mappings: string;
        file: string;
      }
    | string
    | null;
};