Unexpected execution failures with fs_write tool during code refactoring

[blakehurd]

Checks

• I have searched github.com/aws/amazon-q-developer-cli/issues and there are no duplicates of my issue

Operating system

macOS 15.4.1 (24E263)

Expected behaviour

The fs_write tool should properly handle string replacements in code files, especially when replacing string literals with constants during refactoring tasks.

Actual behaviour

When attempting to use fs_write with str_replace to change string literals like "titleCard" to constants like ItemType.TITLE_CARD, the tool reports errors such as "3 occurrences of old_str were found when only 1 is expected" even when targeting specific code blocks.

[chat-transcript]
I understand that the tests are still passing, but we haven't completed updating all the string literals to constants. Let's continue with the cleanup by systematically replacing the remaining string literals with their 

> /compact

> Please continue fixing the string literals. The changes you attempted kept failing

I understand that the previous changes were failing. Let's take a more careful approach to fix the string literals. First, let's examine the files to identify the exact string literals that need to be replaced and understand their context better.

Let me read the current state of the test files to get a clearer picture:
[Tool uses: fs_read]



I need to find the correct path to the test files. Let me check the directory structure:
[Tool uses: execute_bash]

> y


[Tool uses: execute_bash]


[Tool uses: execute_bash]


[Tool uses: execute_bash]

> y


[Tool uses: execute_bash]

> y


[Tool uses: execute_bash]

> n look at this list: 
LiveEventCardTransformerTest.kt:324:            .setType("titleCard")> 
LiveEventCardTransformerTest.kt:345:        assertEquals("titleCard", modifiableWidget.type)> 
LiveEventCardTransformerTest.kt:362:            .setType("titleCard")> 
LiveEventCardTransformerTest.kt:370:            .setType("titleCard")> 
LiveEventCardTransformerTest.kt:378:            .setType("titleCard")

I see the list of string literals that need to be replaced. These are all instances of `"titleCard"` in the Kotlin test files that should be replaced with the constant `ItemType.TITLE_CARD`. Let me help you fix these.

Based on the list, we need to update one file:
1. LiveEventCardTransformerTest.kt

Let's start with....kt:
[Tool uses: fs_read]


[Tool uses: execute_bash]


[Tool uses: fs_read]


[Tool uses: fs_read]



Now I'll update the files to replace the string literals with constants. Let me start with ...kt:
[Tool uses: fs_write]

> y


[Tool uses: fs_write]

> y


[Tool uses: fs_write]

> y



Let me try a more specific approach by targeting each occurrence individually:
[Tool uses: fs_write]

> y


[Tool uses: fs_read]


[Tool uses: fs_read]


[Tool uses: fs_read]


[Tool uses: fs_write]

> y


[Tool uses: execute_bash]

> /issue "unexpected execution failed on fs_write affecting refactoring"

I understand you'd like to report an issue with the `fs_write` tool that's affecting your refactoring efforts. I can help you create a GitHub issue to report this problem.
[Tool uses: report_issue]

(...truncated)

Steps to reproduce

1. Attempt to refactor Kotlin test files by replacing string literals with constants
2. Use fs_write with str_replace command to target specific string replacements
3. Receive error about multiple occurrences when trying to replace specific instances