replacing values with a multi-line string value provides broken yaml format.

[mandelsoft]

Describe the bug

The multi line string is replaced, but the indentation of the string lines is wrong.

To Reproduce

use yaml document:

data:
  value1: orig1
  value2: orig2

replace $.data.value1 by

line1
line2

The result will be

data:
  value1: |-
  line1
  line2
  value2: orig2

instead of

data:
  value1: |-
    line1
    line2
  value2: orig2

The data is parsed with parser.ParseBytes(data, 0). The replace operation is

file, err := parser.ParseBytes(value, 0)
if err != nil {
    return err
}
p, err := yaml.PathString("$.data.value1")
if err != nil {
    return err
}
return p.ReplaceWithFile(doc, file)

Expected behavior provide correct multi-line result

Screenshots If applicable, add screenshots to help explain your problem.

Version Variables

• Go version: 1.22
• go-yaml's Version: v1.11.3

Additional context

The ast nodes provide some strange column values for string value. Especially there is no column info for follow-up value lines. Therefore, the String() method just uses the original string formatting from the target value, which will for sure be wrong in most cases. When replacing a value, only the column value is adapted for the new value, but this cannot be used to serialize follow-up lines.

[Skarlso]

https://github.com/goccy/go-yaml/issues/292

Also reported two years ago without any resolution. :(

[Skarlso]

I'm attempting to see if I can fix this.

[Skarlso]

Reproduced the issue in path_test.go with:

        {
            path: "$.data.value1",
            dst: `
data:
  value1: orig1
  value2: orig2
`,
            src: `
line1
line2
`,
            expected: `
data:
  value1: |-
    line1
    line2
  value2: orig2
`,
        },

I'll attempt to fix the problem.

[Skarlso]

The AST node replace doesn't care how deep it is so it plain does a replace on the node value resulting in a YAML that doesn't work.

[Skarlso]

Tomorrow I'll try to fix this. I have an idea of tracking the deepness recursively for StringNodes for multi-line text. let's see..

[Skarlso]

so I figured out that the library just expects you to pass in the value you require including the right indentation level.

        {
            path: "$.data.value1.orig1",
            dst: `
data:
  value1:
    orig1: orig1.1
  value2: orig2
`,
            src: `|-
      line1
      line2
`,
            expected: `
data:
  value1:
    orig1: |-
      line1
      line2
  value2: orig2
`,
        },

Passes as a test case.

[dee0]

Nice find @Skarlso Can something similar be done when the new value of orig1 is an object instead of a multiline string? I ask because when I stumbled on this problem I was seeing the same problem for an object.

[Skarlso]

Do you have an example?

[Skarlso]

I tried replacing objects, but the marshalling is all over the place. There is virtually no consistency in indentation whatsoever. I can't find a pattern or anything that would make it work. :(

[Skarlso]

Okay, this now worked finally:

        {
            path: "$.data.value1.orig1",
            dst: `
data:
  value1:
    orig1: orig1.1
  value2: orig2
`,
            src: `
orig1:
  newValue:
    - value1
    - value2
`,
            expected: `
data:
  value1:
    orig1:
      orig1:
        newValue:
          - value1
          - value2
  value2: orig2
`,
        },