chore: import upstream snapshot with attribution

tests/repro/repro_issue221.c

@@ -0,0 +1,158 @@
+/*
+ * repro_issue221.c  --  Regression guard for bug #221.
+ *
+ * Bug #221: "'install' command does not work for opencode in windows 11"
+ *
+ * ROOT CAUSE:
+ *   find_in_path (src/cli/cli.c) probed only the bare executable name
+ *   "opencode" for each PATH entry.  On Windows, CLI tools installed via
+ *   mise/npm/scoop ship as extension-bearing shims (.cmd, .ps1, .exe), so
+ *   the bare-name probe never matched and cbm_find_cli("opencode", ...) always
+ *   returned an empty string.  The installer therefore concluded opencode was
+ *   absent and skipped wiring it even when it was present on PATH.
+ *
+ * FIX (commit 0485d3f, "fix(cli): probe Windows PATHEXT variants in
+ *   find_in_path (#221)"):
+ *   On _WIN32, find_in_path now iterates the common PATHEXT variants
+ *   (.exe, .cmd, .bat, .ps1) for each PATH directory after the bare-name
+ *   probe fails, matching whichever extension-qualified file is present.
+ *
+ * REGRESSION GUARD -- expected GREEN on current main (fix is in):
+ *   The fix was committed as 0485d3f and CI (build-windows + test-windows)
+ *   was green before merge.  This test is therefore expected to PASS on the
+ *   current codebase.  It will turn RED if find_in_path is accidentally
+ *   regressed to bare-name-only lookup.
+ *
+ * CROSS-PLATFORM STRATEGY:
+ *   On POSIX: create a plain executable named "opencode" (no extension).
+ *             Bare-name lookup has always worked here, so the test confirms
+ *             cbm_find_cli("opencode", ...) resolves correctly -- the baseline.
+ *   On Windows: create "opencode.cmd" (the most common shim format).
+ *             Before the fix, find_in_path returned "" for this case; after
+ *             the fix it returns the .cmd path -- the regression guard proper.
+ *   Both branches exercise the same public function and assertion; only the
+ *   fixture filename differs.
+ *
+ * NOTE: no slash-star inside this block comment to avoid nested-comment UB.
+ */
+
+#include <foundation/compat.h>
+#include "test_framework.h"
+#include "test_helpers.h"
+#include <cli/cli.h>
+
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+/* ── Minimal local helpers (mirror test_cli.c pattern) ──────────────────── */
+
+static int repro221_write_file(const char *path, const char *content) {
+    FILE *f = fopen(path, "w");
+    if (!f)
+        return -1;
+    fprintf(f, "%s", content);
+    fclose(f);
+    return 0;
+}
+
+/* ── Test ───────────────────────────────────────────────────────────────── */
+
+/*
+ * repro_issue221_opencode_pathext_lookup
+ *
+ * Verify that cbm_find_cli("opencode", ...) resolves the opencode executable
+ * (or its Windows .cmd shim) when the containing directory is on PATH.
+ *
+ * CORRECT BEHAVIOUR (post-fix):
+ *   cbm_find_cli returns a non-empty string whose basename starts with
+ *   "opencode" -- meaning find_in_path found the file.
+ *
+ * BUGGY BEHAVIOUR (pre-fix, Windows only):
+ *   cbm_find_cli returns "" because find_in_path only probed the bare name
+ *   "opencode" and never tried "opencode.cmd" / "opencode.exe" / etc.
+ *
+ * GREEN on current main (fix present): ASSERT fires with a non-empty result.
+ * RED if regressed: ASSERT fires because result is empty.
+ */
+TEST(repro_issue221_opencode_pathext_lookup) {
+    /* Create an isolated temp directory to act as a fake PATH entry. */
+    char tmpdir[256];
+    snprintf(tmpdir, sizeof(tmpdir), "/tmp/repro221-XXXXXX");
+    if (!cbm_mkdtemp(tmpdir))
+        FAIL("cbm_mkdtemp failed");
+
+    /*
+     * Choose the fixture filename to match the platform convention:
+     *   POSIX   -- "opencode"      (plain executable; bare-name lookup)
+     *   Windows -- "opencode.cmd"  (most common shim installed by mise/npm)
+     *
+     * On Windows (pre-fix) find_in_path returned "" for "opencode.cmd"
+     * because only the bare name was probed.  The fix tries .cmd before
+     * moving to the next PATH entry, so the shim is found.
+     */
+#ifdef _WIN32
+    const char *fixture_name = "opencode.cmd";
+    const char *fixture_content = "@echo off\r\nrem fake opencode shim\r\n";
+#else
+    const char *fixture_name = "opencode";
+    const char *fixture_content = "#!/bin/sh\n# fake opencode\n";
+#endif
+
+    char fixture_path[512];
+    snprintf(fixture_path, sizeof(fixture_path), "%s/%s", tmpdir, fixture_name);
+
+    if (repro221_write_file(fixture_path, fixture_content) != 0)
+        FAIL("failed to write opencode fixture");
+
+    /* Make executable (no-op on Windows -- extension decides executability). */
+    th_make_executable(fixture_path);
+
+    /* Swap PATH so only tmpdir is searched, isolating the lookup. */
+    const char *raw_path = getenv("PATH");
+    char *old_path = raw_path ? strdup(raw_path) : NULL;
+    cbm_setenv("PATH", tmpdir, 1);
+
+    /*
+     * The function under test: cbm_find_cli is the public API that calls
+     * find_in_path internally.  We pass a non-existent home_dir so fallback
+     * paths (~/.local/bin etc.) are never tried -- the only possible match
+     * is the fixture file created above.
+     *
+     * Pre-fix (Windows): find_in_path probed "<tmpdir>/opencode" (absent)
+     *   and returned false.  cbm_find_cli returned "".
+     * Post-fix (Windows): find_in_path also probes "<tmpdir>/opencode.cmd"
+     *   (present), finds it, and cbm_find_cli returns the full path.
+     * POSIX (before and after): bare-name probe succeeds immediately.
+     */
+    const char *result = cbm_find_cli("opencode", "/nonexistent-home-dir");
+
+    /* Restore PATH before any assertion so cleanup is always reached. */
+    if (old_path) {
+        cbm_setenv("PATH", old_path, 1);
+        free(old_path);
+    }
+
+    /*
+     * PRIMARY ASSERTION -- regression guard for #221.
+     *
+     * cbm_find_cli MUST return a non-empty path that contains "opencode".
+     *
+     * GREEN (current main, fix present): result points to the fixture file.
+     * RED (if regressed to bare-name-only on Windows): result is "".
+     */
+    ASSERT_FALSE(result == NULL);
+    ASSERT(result[0] != '\0');
+    ASSERT(strstr(result, "opencode") != NULL);
+
+    /* Cleanup fixture and temp dir. */
+    (void)remove(fixture_path);
+    (void)rmdir(tmpdir);
+
+    PASS();
+}
+
+/* ── Suite ──────────────────────────────────────────────────────────────── */
+SUITE(repro_issue221) {
+    RUN_TEST(repro_issue221_opencode_pathext_lookup);
+}