V4 Story: Line Auditor

Statically tracks specific method calls (like app.use middleware hooks) on a line-by-line basis.

🧩 Custom Scan 🔎 Line Constraints 🔥 Target Filter

1. What

The Line Auditor Story (V4) utilizes multiline regex flags to identify configuration lines, method invocations, or middleware mount hooks (such as app.use(...)) strictly formatted at the start of code lines.

2. How

The auditor accepts code content along with a multiline RegExp pattern. By using the multiline flag m combined with line anchors ^ or $, it processes search strings line-by-line to extract matching method statements while ignoring mid-line strings or commented references.

Key Parameters:

fileContent (string): The code content to scan.
searchString (RegExp): A multiline regular expression using the global flag (e.g. /^[ \t]*app\.use\s*\(/gm).

3. Example

Below is the configuration and corresponding matches output:

Line Auditor Code

import patternCollector from 'pattern-collector';

const matches = patternCollector({
  fileContent: codeText,
  searchString: /^[ \t]*app\.use\s*\(/gm
});

Output Results

[
  "app.use("
]

🎮 Live Playground

Input code and a line RegExp to see targeted line matches immediately.

Source Code

Line RegExp Pattern

Matches Result

Click "Collect Patterns" to see results.

4. Dependency Diagram

The diagram below represents how the line analyzer accesses the base package in the ecosystem to collect matching lines:

graph TD user_code["line-auditor.html (V4 Story)"] --> pc_anyjs["pattern-collector-anyjs"] pc_anyjs --> pc["pattern-collector"] style user_code fill:#1e293b,stroke:#38bdf8,stroke-width:2px,color:#f8fafc style pc fill:#020617,stroke:#818cf8,stroke-width:1px,color:#cbd5e1 classDef default fill:#0f172a,stroke:#334155,color:#f8fafc;