feat(cli): gate wheels doctor mixin-collision detail behind --verbose (#2287)

* feat(cli): add --verbose gating to wheels doctor mixin collisions

Default output now shows a single-line count summary; full per-collision
detail is enumerated only under `wheels doctor --verbose`. Structured
collision entries live on `results.mixinCollisions` so the service stays
presentation-neutral.

Closes #2261

* fix(cli): gate packages extraction on tar exit code, not stderr

`$extract()` threw on any non-empty stderr, which tripped on GNU tar's
informational warnings ("Ignoring unknown extended header keyword
'LIBARCHIVE.xattr.com.apple.provenance'") when extracting macOS-authored
tarballs on Linux. Extraction still succeeded — exit code 0 — so the
stderr check was spurious.

Switch to cfexecute's `result=` arg and throw only when `exitCode != 0`,
preserving stderr in extendedInfo for diagnostics.

Fixes 4 CI errors in InstallerSpec / PackagesMainCliSpec that were
previously masked by TestBox's negative totalError accounting.

Author: bpamiri

cli/lucli/Module.cfc

@@ -1237,6 +1237,18 @@ component extends="modules.BaseModule" {
 			out("");
 		}
 
+		// Mixin collision detail (verbose only)
+		if (verbose && structKeyExists(results, "mixinCollisions") && arrayLen(results.mixinCollisions)) {
+			out("Mixin collisions (#arrayLen(results.mixinCollisions)#):", "yellow");
+			for (var c in results.mixinCollisions) {
+				out(
+					"  ! method '#c.method#' on '#c.target#' provided by #c.firstSource# '#c.firstName#' is overwritten by #c.secondSource# '#c.secondName#'. Acknowledge via provides.overrides to silence.",
+					"yellow"
+				);
+			}
+			out("");
+		}
+
 		// Passed (verbose only, or when no issues)
 		if (verbose || (results.status == "HEALTHY")) {
 			out("Passed (#arrayLen(results.passed)#):", "green");

cli/lucli/services/Doctor.cfc

@@ -19,7 +19,7 @@ component {
 	 * Run all health checks and return categorized results.
 	 */
 	public struct function runChecks() {
-		var results = {issues: [], warnings: [], passed: []};
+		var results = {issues: [], warnings: [], passed: [], mixinCollisions: []};
 
 		checkRequiredDirs(results);
 		checkRecommendedDirs(results);
@@ -303,15 +303,24 @@ component {
 			for (var i = 2; i <= arrayLen(entries); i++) {
 				var second = entries[i];
 				collisionCount++;
-				arrayAppend(
-					arguments.results.warnings,
-					"Mixin collision: method '#second.method#' on '#second.target#' provided by #first.source# '#first.name#' is overwritten by #second.source# '#second.name#'. Acknowledge via provides.overrides to silence."
-				);
+				arrayAppend(arguments.results.mixinCollisions, {
+					target: second.target,
+					method: second.method,
+					firstName: first.name,
+					firstSource: first.source,
+					secondName: second.name,
+					secondSource: second.source
+				});
 				first = second;
 			}
 		}
 
-		if (collisionCount == 0 && (directoryExists(vendorDir) || directoryExists(pluginsDir))) {
+		if (collisionCount > 0) {
+			arrayAppend(
+				arguments.results.warnings,
+				"#collisionCount# mixin collision(s) detected — run 'wheels doctor --verbose' for details"
+			);
+		} else if (directoryExists(vendorDir) || directoryExists(pluginsDir)) {
 			arrayAppend(arguments.results.passed, "No static mixin collisions detected in vendor/ or plugins/");
 		}
 	}

cli/lucli/services/packages/Installer.cfc

@@ -162,13 +162,15 @@ component {
 
 	private void function $extract(required string tarballPath, required string destDir) {
 		// Wrap in a try so a missing `tar` produces a clear error message.
+		local.result = {};
 		try {
 			cfexecute(
 				name = "tar",
 				arguments = "-xzf #arguments.tarballPath# -C #arguments.destDir#",
 				timeout = 120,
 				variable = "local.stdout",
-				errorVariable = "local.stderr"
+				errorVariable = "local.stderr",
+				result = "local.result"
 			);
 		} catch (any e) {
 			Throw(
@@ -177,11 +179,17 @@ component {
 				extendedInfo = e.message
 			);
 		}
-		if (StructKeyExists(local, "stderr") && Len(Trim(local.stderr))) {
+		// Gate on exit code, not stderr presence. GNU tar on Linux prints
+		// informational warnings ("Ignoring unknown extended header keyword
+		// 'LIBARCHIVE.xattr.com.apple.provenance'") for macOS-authored
+		// tarballs while still exiting 0 and extracting cleanly.
+		var exitCode = StructKeyExists(local.result, "exitCode") ? local.result.exitCode : 0;
+		if (exitCode != 0) {
+			var stderr = StructKeyExists(local, "stderr") ? local.stderr : "";
 			Throw(
 				type = "Wheels.Packages.ExtractionFailed",
-				message = "tar reported an error during extraction.",
-				extendedInfo = local.stderr
+				message = "tar exited with code #exitCode# during extraction.",
+				extendedInfo = stderr
 			);
 		}
 	}

cli/lucli/tests/specs/services/DoctorSpec.cfc

@@ -244,8 +244,9 @@ component extends="wheels.wheelstest.system.BaseSpec" {
 					var root = makeProjectRoot();
 					var doctor = new cli.lucli.services.Doctor(projectRoot = root);
 					var results = doctor.runChecks();
+					expect(arrayLen(results.mixinCollisions)).toBe(0);
 					var combined = arrayToList(results.warnings, " ");
-					expect(combined).notToInclude("Mixin collision");
+					expect(combined).notToInclude("mixin collision");
 					directoryDelete(root, true);
 				});
 
@@ -257,38 +258,55 @@ component extends="wheels.wheelstest.system.BaseSpec" {
 					var doctor = new cli.lucli.services.Doctor(projectRoot = root);
 					var results = doctor.runChecks();
 
+					expect(arrayLen(results.mixinCollisions)).toBe(0);
 					var warningText = arrayToList(results.warnings, " ");
-					expect(warningText).notToInclude("Mixin collision");
+					expect(warningText).notToInclude("mixin collision");
 					var passedText = arrayToList(results.passed, " ");
 					expect(passedText).toInclude("No static mixin collisions");
 					directoryDelete(root, true);
 				});
 
-				it("warns when two packages provide the same method on the same target", () => {
+				it("emits summary in warnings and detail in mixinCollisions when packages collide", () => {
 					var root = makeProjectRoot();
 					makePackage(root, "pkgA", "controller", "$shared", []);
 					makePackage(root, "pkgB", "controller", "$shared", []);
 
 					var doctor = new cli.lucli.services.Doctor(projectRoot = root);
 					var results = doctor.runChecks();
 
+					// Default output: count summary only, no inline detail
 					var warningText = arrayToList(results.warnings, " ");
-					expect(warningText).toInclude("Mixin collision");
-					expect(warningText).toInclude("$shared");
-					expect(warningText).toInclude("controller");
+					expect(warningText).toInclude("mixin collision(s) detected");
+					expect(warningText).toInclude("--verbose");
+					expect(warningText).notToInclude("$shared");
+
+					// Verbose-dump data on the results struct
+					expect(arrayLen(results.mixinCollisions)).toBe(1);
+					var c = results.mixinCollisions[1];
+					expect(c.method).toBe("$shared");
+					expect(c.target).toBe("controller");
+					// directoryList() iteration order isn't guaranteed across filesystems,
+					// so assert both packages are present without fixing which came first.
+					var participants = [c.firstName, c.secondName];
+					arraySort(participants, "textnocase");
+					expect(participants[1]).toBe("pkgA");
+					expect(participants[2]).toBe("pkgB");
+					expect(c.firstSource).toBe("package");
+					expect(c.secondSource).toBe("package");
 					directoryDelete(root, true);
 				});
 
-				it("suppresses warning when overriding package declares provides.overrides", () => {
+				it("suppresses warning and detail when overriding package declares provides.overrides", () => {
 					var root = makeProjectRoot();
 					makePackage(root, "pkgA", "controller", "$shared", []);
 					makePackage(root, "pkgB", "controller", "$shared", ["$shared"]);
 
 					var doctor = new cli.lucli.services.Doctor(projectRoot = root);
 					var results = doctor.runChecks();
 
+					expect(arrayLen(results.mixinCollisions)).toBe(0);
 					var warningText = arrayToList(results.warnings, " ");
-					expect(warningText).notToInclude("Mixin collision");
+					expect(warningText).notToInclude("mixin collision");
 					directoryDelete(root, true);
 				});