refactor(shared): dedupe config path eval

src/shared/config-eval.ts

@@ -0,0 +1,71 @@
+import fs from "node:fs";
+import path from "node:path";
+
+export function isTruthy(value: unknown): boolean {
+  if (value === undefined || value === null) {
+    return false;
+  }
+  if (typeof value === "boolean") {
+    return value;
+  }
+  if (typeof value === "number") {
+    return value !== 0;
+  }
+  if (typeof value === "string") {
+    return value.trim().length > 0;
+  }
+  return true;
+}
+
+export function resolveConfigPath(config: unknown, pathStr: string): unknown {
+  const parts = pathStr.split(".").filter(Boolean);
+  let current: unknown = config;
+  for (const part of parts) {
+    if (typeof current !== "object" || current === null) {
+      return undefined;
+    }
+    current = (current as Record<string, unknown>)[part];
+  }
+  return current;
+}
+
+export function isConfigPathTruthyWithDefaults(
+  config: unknown,
+  pathStr: string,
+  defaults: Record<string, boolean>,
+): boolean {
+  const value = resolveConfigPath(config, pathStr);
+  if (value === undefined && pathStr in defaults) {
+    return defaults[pathStr] ?? false;
+  }
+  return isTruthy(value);
+}
+
+export function resolveRuntimePlatform(): string {
+  return process.platform;
+}
+
+function windowsPathExtensions(): string[] {
+  const raw = process.env.PATHEXT;
+  const list =
+    raw !== undefined ? raw.split(";").map((v) => v.trim()) : [".EXE", ".CMD", ".BAT", ".COM"];
+  return ["", ...list.filter(Boolean)];
+}
+
+export function hasBinary(bin: string): boolean {
+  const pathEnv = process.env.PATH ?? "";
+  const parts = pathEnv.split(path.delimiter).filter(Boolean);
+  const extensions = process.platform === "win32" ? windowsPathExtensions() : [""];
+  for (const part of parts) {
+    for (const ext of extensions) {
+      const candidate = path.join(part, bin + ext);
+      try {
+        fs.accessSync(candidate, fs.constants.X_OK);
+        return true;
+      } catch {
+        // keep scanning
+      }
+    }
+  }
+  return false;
+}