feat(bash): implement FUNCNAME special variable (#248)

## Summary
- Implement `FUNCNAME` bash array variable that reflects the function
call stack
- `FUNCNAME[0]` is the current function, `FUNCNAME[1]` is the caller,
etc.
- At top level, `FUNCNAME` is empty (length 0)
- Array is set from the call stack before function body execution and
restored after

## Test plan
- [x] 5 new spec tests: basic name, call stack, nesting depth, empty
outside functions, restored after return
- [x] All 1204 spec tests pass (1199 pass, 5 skip)
- [x] `cargo clippy` and `cargo fmt` clean

Co-authored-by: Claude <noreply@anthropic.com>

Author: chaliy

crates/bashkit/src/interpreter/mod.rs

@@ -2431,13 +2431,30 @@ impl Interpreter {
                 positional: args.clone(),
             });
 
+            // Set FUNCNAME array from call stack (index 0 = current, 1 = caller, ...)
+            let funcname_arr: HashMap<usize, String> = self
+                .call_stack
+                .iter()
+                .rev()
+                .enumerate()
+                .map(|(i, f)| (i, f.name.clone()))
+                .collect();
+            let prev_funcname = self.arrays.insert("FUNCNAME".to_string(), funcname_arr);
+
             // Execute function body
             let mut result = self.execute_command(&func_def.body).await?;
 
             // Pop call frame and function counter
             self.call_stack.pop();
             self.counters.pop_function();
 
+            // Restore previous FUNCNAME (or set from remaining stack)
+            if self.call_stack.is_empty() {
+                self.arrays.remove("FUNCNAME");
+            } else if let Some(prev) = prev_funcname {
+                self.arrays.insert("FUNCNAME".to_string(), prev);
+            }
+
             // Handle return - convert Return control flow to exit code
             if let ControlFlow::Return(code) = result.control_flow {
                 result.exit_code = code;

crates/bashkit/tests/spec_cases/bash/functions.test.sh

@@ -159,3 +159,47 @@ echo "after outer: $x"
 in outer: local_val
 after outer: global
 ### end
+
+### func_funcname_basic
+# FUNCNAME[0] is current function name
+myfunc() { echo "${FUNCNAME[0]}"; }
+myfunc
+### expect
+myfunc
+### end
+
+### func_funcname_call_stack
+# FUNCNAME array reflects call stack
+inner() { echo "${FUNCNAME[@]}"; }
+outer() { inner; }
+outer
+### expect
+inner outer
+### end
+
+### func_funcname_depth
+# FUNCNAME array length matches nesting depth
+a() { echo "${#FUNCNAME[@]}"; }
+b() { a; }
+c() { b; }
+c
+### expect
+3
+### end
+
+### func_funcname_empty_outside
+# FUNCNAME is empty outside functions
+echo "${#FUNCNAME[@]}"
+### expect
+0
+### end
+
+### func_funcname_restored
+# FUNCNAME is cleared after function returns
+f() { echo "in: ${FUNCNAME[0]}"; }
+f
+echo "out: ${#FUNCNAME[@]}"
+### expect
+in: f
+out: 0
+### end

specs/009-implementation-status.md

@@ -103,16 +103,16 @@ Bashkit implements IEEE 1003.1-2024 Shell Command Language. See
 
 ## Spec Test Coverage
 
-**Total spec test cases:** 1199 (1194 pass, 5 skip)
+**Total spec test cases:** 1204 (1199 pass, 5 skip)
 
 | Category | Cases | In CI | Pass | Skip | Notes |
 |----------|-------|-------|------|------|-------|
-| Bash (core) | 838 | Yes | 833 | 5 | `bash_spec_tests` in CI |
+| Bash (core) | 843 | Yes | 838 | 5 | `bash_spec_tests` in CI |
 | AWK | 96 | Yes | 96 | 0 | loops, arrays, -v, ternary, field assign, getline, %.6g |
 | Grep | 76 | Yes | 76 | 0 | -z, -r, -a, -b, -H, -h, -f, -P, --include, --exclude, binary detect |
 | Sed | 75 | Yes | 75 | 0 | hold space, change, regex ranges, -E |
 | JQ | 114 | Yes | 114 | 0 | reduce, walk, regex funcs, --arg/--argjson, combined flags, input/inputs, env |
-| **Total** | **1199** | **Yes** | **1194** | **5** | |
+| **Total** | **1204** | **Yes** | **1199** | **5** | |
 
 ### Bash Spec Tests Breakdown
 
@@ -136,7 +136,7 @@ Bashkit implements IEEE 1003.1-2024 Shell Command Language. See
 | errexit.test.sh | 8 | set -e tests |
 | fileops.test.sh | 21 | |
 | find.test.sh | 10 | file search |
-| functions.test.sh | 17 | local dynamic scoping, nested writes |
+| functions.test.sh | 22 | local dynamic scoping, nested writes, FUNCNAME call stack |
 | getopts.test.sh | 9 | POSIX option parsing, combined flags, silent mode |
 | globs.test.sh | 12 | for-loop glob expansion, recursive `**` |
 | headtail.test.sh | 14 | |

supply-chain/config.toml

@@ -962,6 +962,10 @@ criteria = "safe-to-deploy"
 version = "0.8.9"
 criteria = "safe-to-deploy"
 
+[[exemptions.regex-syntax]]
+version = "0.8.10"
+criteria = "safe-to-deploy"
+
 [[exemptions.reqwest]]
 version = "0.13.2"
 criteria = "safe-to-deploy"