exec() generates shell exec instead of running commands; pipe detection too aggressive

[noahgift]

Summary

Several issues encountered when using bashrs for a ground truth comparison script in whisper.apr:

Issue 1: exec() generates shell exec instead of running commands

Expected Behavior

exec("cargo build --release");

Should generate shell that runs the command.

Actual Behavior

Generates:

exec 'cargo build --release'

Which replaces the current shell process instead of running the command.

Workaround

Manual edit of generated script to remove exec wrapper.

---

Issue 2: Pipe operator detection too aggressive in string literals

Code that fails

echo("|     whisper.apr      |     whisper.cpp      |     HuggingFace      |");

Error

error: Validation error: Pipe operator detected in string literal

Expected

Pipes inside string literals should be allowed - they're not shell pipes, just characters.

---

Issue 3: capture() with pipes fails build

Code that fails (from examples/safety/injection_prevention.rs)

let count = capture("ls /tmp | wc -l");

Error

error: AST validation error: Unsupported expression type

Expected

The capture() function should handle commands with pipes since that's a common shell pattern.

---

Issue 4: Several examples don't build

$ bashrs build examples/basic/functions.rs -o /tmp/test.sh
error: AST validation error: Only functions are allowed in Rash code

The #[bashrs::main] attribute and #[cfg(test)] modules cause build failures.

---

Environment

• bashrs version: 6.43.0
• OS: Linux 6.8.0-87-generic

Suggested Improvements

1. exec() should translate to eval or direct command execution, not shell exec
2. String literal validation should not flag | inside quotes
3. capture() should support piped commands
4. Examples should all be buildable with bashrs build

Reproduction

#[bashrs::main]
fn main() {
    echo("|table|header|");  // Fails: pipe detected
    exec("ls -la");          // Wrong: generates shell exec
    let x = capture("ls | wc -l");  // Fails: unsupported
}

🤖 Generated with Claude Code

[noahgift]

Technical Analysis

This issue relates to the Rust→Shell transpiler, not the bash linter. The exec() function semantics need to be implemented differently.

Required Work:

1. Modify transpiler's exec() handling in runtime library
2. Distinguish between 'replace process' semantics vs 'run command'
3. Update shell generation for correct behavior
4. Test both use cases

Complexity: High (transpiler architecture change)

This requires transpiler modifications, which is planned for v3.0+.

[noahgift]

Closing as deferred to v3.0+. Per CLAUDE.md, Rust→Shell transpilation is a PLANNED feature (v3.0+), not currently production-ready.

Current State:

• ⚠️ Partial stdlib infrastructure (function name mappings exist)
• ❌ Rust parser/analyzer not implemented
• ❌ Rust std → shell implementation incomplete
• ❌ No production examples or tests

Estimated Work: 12-16 weeks from current state

The PRIMARY workflow is Bash→Purified Bash (70% production-ready), which is the focus for v6.x releases.