feat(core/formatters): support variable resolution in replace() first argument

[kRYstall9]

This feature makes the replace method work with any formatter variable, such as {stream.title}, {addon.name} etc...
This might be useful for any person who wants to take their custom formatter any step forward.

AS IS

filename: Movie.Title.2023.2160p.BluRay.HEVC.DV.TrueHD.Atmos.7.1.iTA.ENG-GROUP.mkv
{stream.filename::replace('.', ' ')::replace('{stream.title}', '')} replaces all the dots with a whitespace but it doesn't replace the stream title (Movie Title in this case) with an empty string

TO BE

filename: Movie.Title.2023.2160p.BluRay.HEVC.DV.TrueHD.Atmos.7.1.iTA.ENG-GROUP.mkv
{stream.filename::replace('.', ' ')::replace('{stream.title}', '')} replaces all the dots with a whitespace and it does replace the stream title (Movie Title in this case) with an empty string.
So it will result in 2023 2160p BluRay HEVC DV TrueHD Atmos 7 1 iTA ENG-GROUP mkv

Resolves #790

Summary by CodeRabbit

• Improvements
  • Replace operations now resolve dynamic placeholders at runtime before performing replacements; errors or empty resolutions preserve the original placeholder to avoid unintended broad matches.
  • Modifier application carries runtime value-resolution context through the formatting pipeline, allowing multi-modifier chains to operate on resolved values.
  • No breaking public API changes.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

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📥 Commits

Reviewing files that changed from the base of the PR and between 8025bc1 and 2b84426.

📒 Files selected for processing (1)

• packages/core/src/formatters/base.ts

🚧 Files skipped from review as they are similar to previous changes (1)

• packages/core/src/formatters/base.ts

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Walkthrough

This change makes replace(...) resolve inner {variable} expressions using parseModifiedVariable(parseValue) before replacing, and threads an optional parseValue through applySingleModifier to support modifier-aware resolution.

Changes

Cohort / File(s)	Summary
Formatter core packages/core/src/formatters/base.ts	Resolve {variable}-style keys inside replace(...) by parsing the inner variable with parseModifiedVariable(parseValue); if resolution is error/null/empty, keep original key. Extend internal applySingleModifier signature to accept optional parseValue and propagate it through modifier application calls.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Possibly related PRs

• Refactoring BaseFormatter for Readability & Ease of Changes #382: Modifies packages/core/src/formatters/base.ts and the BaseFormatter modifier application path, closely related to these changes.

Suggested reviewers

• Viren070

Poem

🐰 I hopped through strings and curly braces bright,
I chased the inner names until they came to light.
Replacements now follow the rabbit's trail,
No empty swaps, no accidental gale.
A nimble hop, a tidy file — all right!

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and specifically describes the main change: enabling variable resolution in the replace() method's first argument, which directly aligns with the core functionality introduced in this PR.
Linked Issues check	✅ Passed	The PR implementation fully satisfies issue #790 requirements: variable expressions are resolved before replacement, allowing dynamic substitution of metadata-derived substrings instead of only hardcoded strings.
Out of Scope Changes check	✅ Passed	All changes remain focused on the replace() method variable resolution feature; the modification to applySingleModifier signature and parseValue propagation are necessary implementation details for this feature.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@packages/core/src/formatters/base.ts`:
- Around line 899-917: The dynamic replace path can resolve a formatter variable
to an empty string and then call variable.replaceAll('', replaceKey), which
inserts replaceKey between every character; in the replace handling in base.ts
(the branch using shouldBeUndefined, key, replaceKey and
parseModifiedVariable/parseValue) add a guard after resolving resolvedKey: if
resolvedKey is an empty string, short-circuit and return the original variable
(no-op) instead of calling variable.replaceAll; keep existing behavior for
non-empty resolvedKey and preserve use of parseModifiedVariable/parseValue.

---

ℹ️ Review info

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Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 2c7bdc5b-b11e-4a3b-905c-54003377c1ea

📥 Commits

Reviewing files that changed from the base of the PR and between 2ce0b3a and fdddcc5.

📒 Files selected for processing (1)

• packages/core/src/formatters/base.ts

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@packages/core/src/formatters/base.ts`:
- Around line 899-920: The code currently falls back to using the literal
"{...}" placeholder as the search key when parseModifiedVariable resolution
fails, which can silently become a no-op or corrupt strings; inside the branch
that handles key.startsWith('{') && key.endsWith('}') replace the current
swallowing logic with an explicit guard: after calling
this.parseModifiedVariable(innerVar, fullStringModifiers) and invoking
resolvedFn(parseValue), if resolved.error is present OR resolved.result == null
then return variable immediately (do not proceed to replaceAll); only set
resolvedKey = String(resolved.result) and continue if resolved.result is
non-null and non-empty, otherwise return variable to avoid empty-string
replacement. Ensure this change is applied where resolvedKey, resolved,
parseModifiedVariable, and variable.replaceAll are referenced.

---

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⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 47256978-f181-41b0-84c7-838f30e83fc1

📥 Commits

Reviewing files that changed from the base of the PR and between fdddcc5 and 4d69935.

📒 Files selected for processing (1)

• packages/core/src/formatters/base.ts

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@packages/core/src/formatters/base.ts`:
- Around line 899-921: The guard allowing malformed splits should be tightened:
in the replace-argument handling (the block using variables key, replaceKey,
shouldBeUndefined inside the formatter method that calls
this.parseModifiedVariable and ultimately does variable.replaceAll), change the
condition from if (!shouldBeUndefined && key && replaceKey !== undefined) to
require shouldBeUndefined === undefined (or implement a small top-level scanner
to parse the two arguments instead of content.split), so that quoted/nested
commas (e.g., replace('{stream.title::replace('.', ' ')}', '')) do not slip
through and produce broken key/replaceKey fragments; ensure the rest of the
logic (resolving {var} via this.parseModifiedVariable, checking
resolved.error/result, and using resolvedKey.length check before
variable.replaceAll) remains the same.

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 04e2e25d-f68a-4530-a7c6-055e8b10d840

📥 Commits

Reviewing files that changed from the base of the PR and between 4d69935 and 8025bc1.

📒 Files selected for processing (1)

• packages/core/src/formatters/base.ts

[kRYstall9]

Hi @Viren070! I've addressed all the CodeRabbit suggestions. Could you take a look when you have a chance? Thanks!