fix(pipeline): resolve PSR-4 imports to exact class files

Preserve import kinds and resolve class imports through Composer prefixes
to the existing target class file, including autoload-dev mappings.

Refs #1186

Signed-off-by: Martin Vogel <martin.vogel.tech@gmail.com>

internal/cbm/cbm.h

@@ -304,10 +304,20 @@ typedef struct {
                                      // guard's unique-name exemption. Default false.
 } CBMCall;
 
+// What an import statement names, when the syntax says so. Only PHP's
+// `use function` / `use const` set a non-default kind today: they name a
+// namespace MEMBER, so they must never be mapped to a class file (#1186).
+typedef enum {
+    CBM_IMPORT_KIND_DEFAULT = 0, // module / class / namespace (language default)
+    CBM_IMPORT_KIND_FUNCTION,    // PHP `use function A\b`
+    CBM_IMPORT_KIND_CONST,       // PHP `use const A\B`
+} CBMImportKind;
+
 typedef struct {
     const char *local_name;  // local alias or name
     const char *module_path; // resolved module path / QN
     bool is_default;         // ES default import (`import X from "Y"`), JS/TS only (#1916)
+    CBMImportKind kind;      // CBM_IMPORT_KIND_DEFAULT unless the syntax names a member kind
 } CBMImport;
 
 typedef enum {

internal/cbm/extract_imports.c

@@ -1205,7 +1205,29 @@ static void parse_wolfram_imports(CBMExtractCtx *ctx) {
 // require/include forms remain `expression_statement`s and are still handled by
 // the text fallback.  Take the first qualified_name/name descendant of each
 // clause as the module path.
-static void emit_php_use_clause(CBMExtractCtx *ctx, TSNode clause, const char *group_prefix) {
+// `use function` / `use const` carry the keyword as an anonymous direct child
+// of the declaration (flat form) or of the clause (grouped form
+// `use A\{function f, const C, K}`). DEFAULT when neither is present.
+static CBMImportKind php_use_kind(TSNode node) {
+    uint32_t n = ts_node_child_count(node);
+    for (uint32_t i = 0; i < n; i++) {
+        TSNode c = ts_node_child(node, i);
+        if (ts_node_is_named(c)) {
+            continue;
+        }
+        const char *k = ts_node_type(c);
+        if (strcmp(k, "function") == 0) {
+            return CBM_IMPORT_KIND_FUNCTION;
+        }
+        if (strcmp(k, "const") == 0) {
+            return CBM_IMPORT_KIND_CONST;
+        }
+    }
+    return CBM_IMPORT_KIND_DEFAULT;
+}
+
+static void emit_php_use_clause(CBMExtractCtx *ctx, TSNode clause, const char *group_prefix,
+                                CBMImportKind decl_kind) {
     CBMArena *a = ctx->arena;
     // The path node is the qualified_name / namespace_name / name child.
     TSNode path_node = clause;
@@ -1230,12 +1252,14 @@ static void emit_php_use_clause(CBMExtractCtx *ctx, TSNode clause, const char *g
     TSNode alias = ts_node_child_by_field_name(clause, TS_FIELD("alias"));
     const char *local =
         !ts_node_is_null(alias) ? cbm_node_text(a, alias, ctx->source) : path_last(a, path);
-    CBMImport imp = {.local_name = local, .module_path = path};
+    CBMImportKind kind = decl_kind != CBM_IMPORT_KIND_DEFAULT ? decl_kind : php_use_kind(clause);
+    CBMImport imp = {.local_name = local, .module_path = path, .kind = kind};
     cbm_imports_push(&ctx->result->imports, a, imp);
 }
 
 static void emit_php_use_decl(CBMExtractCtx *ctx, TSNode decl) {
     CBMArena *a = ctx->arena;
+    const CBMImportKind decl_kind = php_use_kind(decl);
     // Grouped form: namespace_use_group with a leading prefix qualified_name.
     TSNode group = decl;
     if (find_first_descendant_of(decl, "namespace_use_group", &group)) {
@@ -1257,7 +1281,7 @@ static void emit_php_use_decl(CBMExtractCtx *ctx, TSNode decl) {
             const char *ck = ts_node_type(clause);
             if (strcmp(ck, "namespace_use_group_clause") == 0 ||
                 strcmp(ck, "namespace_use_clause") == 0) {
-                emit_php_use_clause(ctx, clause, prefix);
+                emit_php_use_clause(ctx, clause, prefix, decl_kind);
             }
         }
         return;
@@ -1268,13 +1292,13 @@ static void emit_php_use_decl(CBMExtractCtx *ctx, TSNode decl) {
     for (uint32_t i = 0; i < dc; i++) {
         TSNode clause = ts_node_named_child(decl, i);
         if (strcmp(ts_node_type(clause), "namespace_use_clause") == 0) {
-            emit_php_use_clause(ctx, clause, NULL);
+            emit_php_use_clause(ctx, clause, NULL, decl_kind);
             any = true;
         }
     }
     if (!any) {
         // Some grammar versions inline the path directly under the declaration.
-        emit_php_use_clause(ctx, decl, NULL);
+        emit_php_use_clause(ctx, decl, NULL, decl_kind);
     }
 }
 

src/pipeline/pass_pkgmap.c

@@ -440,9 +440,12 @@ static void parse_pyproject_toml(const char *source, int source_len, const char
     }
 }
 
-/* Extract PSR-4 autoload entries from composer.json root. */
-static void extract_psr4(yyjson_val *root, const char *dir, cbm_pkg_entries_t *entries) {
-    yyjson_val *autoload = yyjson_obj_get(root, "autoload");
+/* Extract PSR-4 entries from one composer.json autoload section ("autoload"
+ * or "autoload-dev": composer registers both, so test namespaces such as
+ * Tests\ map to their directory as well). */
+static void extract_psr4(yyjson_val *root, const char *section, const char *dir,
+                         cbm_pkg_entries_t *entries) {
+    yyjson_val *autoload = yyjson_obj_get(root, section);
     if (!yyjson_is_obj(autoload)) {
         return;
     }
@@ -459,6 +462,12 @@ static void extract_psr4(yyjson_val *root, const char *dir, cbm_pkg_entries_t *e
         }
         const char *ns_prefix = yyjson_get_str(key);
         const char *ns_dir = yyjson_get_str(val);
+        while (ns_dir[0] == '.' && ns_dir[SKIP_ONE] == '/') {
+            ns_dir += PAIR_LEN; /* "./src/" names src/ */
+        }
+        if (strcmp(ns_dir, ".") == 0) {
+            ns_dir = ""; /* "." names the manifest's own directory */
+        }
         char ns_entry[PKGMAP_PATH_BUF];
         if (dir[0]) {
             snprintf(ns_entry, sizeof(ns_entry), "%s/%s", dir, ns_dir);
@@ -497,7 +506,8 @@ static void parse_composer_json(const char *source, int source_len, const char *
         }
     }
 
-    extract_psr4(root, dir, entries);
+    extract_psr4(root, "autoload", dir, entries);
+    extract_psr4(root, "autoload-dev", dir, entries);
 
     free(dir);
     yyjson_doc_free(doc);
@@ -987,6 +997,12 @@ bool cbm_pkgmap_try_parse(const char *basename, const char *rel_path, const char
 
 /* ── Merge: per-worker entries → hash table ────────────────────── */
 
+/* A composer.json `autoload.psr-4` key: a namespace prefix ending in '\\'. */
+static bool pkgmap_is_psr4_prefix(const char *pkg_name) {
+    size_t n = pkg_name ? strlen(pkg_name) : 0;
+    return n > 0 && pkg_name[n - SKIP_ONE] == '\\';
+}
+
 CBMHashTable *cbm_pkgmap_build(cbm_pkg_entries_t *worker_entries, int worker_count,
                                const char *project_name) {
     /* Count total entries */
@@ -1004,8 +1020,14 @@ CBMHashTable *cbm_pkgmap_build(cbm_pkg_entries_t *worker_entries, int worker_cou
     for (int w = 0; w < worker_count; w++) {
         cbm_pkg_entries_t *we = &worker_entries[w];
         for (int i = 0; i < we->count; i++) {
-            /* Convert entry_rel to QN: project.dir.parts */
-            char *qn = cbm_pipeline_fqn_module(project_name, we->items[i].entry_rel);
+            /* Convert entry_rel to QN: project.dir.parts. A PSR-4 namespace
+             * prefix (key ends in '\\') keeps its repo-relative DIRECTORY
+             * instead: its readers map `Prefix\Sub\Class` onto a file path
+             * (<dir>/Sub/Class.php), which a dotted QN cannot express (#1186). */
+            const char *entry_rel = we->items[i].entry_rel;
+            char *qn = pkgmap_is_psr4_prefix(we->items[i].pkg_name)
+                           ? cbm_strndup(entry_rel, strlen(entry_rel))
+                           : cbm_pipeline_fqn_module(project_name, entry_rel);
             if (!qn) {
                 continue;
             }
@@ -1355,7 +1377,8 @@ static char *resolve_dot_prefix(CBMHashTable *map, const char *module_path,
 }
 
 /* Try backslash-based prefix matching (PHP PSR-4: App\\Controllers\\Foo).
- * Returns heap QN or NULL. */
+ * The map value of a PSR-4 prefix is its repo-relative directory (see
+ * cbm_pkgmap_build). Returns heap QN or NULL. */
 static char *resolve_backslash_prefix(CBMHashTable *map, const char *module_path,
                                       const char *project_name) {
     char *buf = strdup(module_path);
@@ -1375,7 +1398,8 @@ static char *resolve_backslash_prefix(CBMHashTable *map, const char *module_path
         }
         const char *subpath = module_path + (size_t)(bs - buf) + SKIP_ONE;
         char path_result[PKGMAP_PATH_BUF];
-        snprintf(path_result, sizeof(path_result), "%s/%s", base_dir, subpath);
+        snprintf(path_result, sizeof(path_result), "%s%s%s", base_dir, base_dir[0] ? "/" : "",
+                 subpath);
         for (char *c = path_result; *c; c++) {
             if (*c == '\\') {
                 *c = '/';
@@ -2025,6 +2049,91 @@ static const cbm_gbuf_node_t *resolve_sibling_file(const cbm_pipeline_ctx_t *ctx
     return found;
 }
 
+/* ── PHP PSR-4 class imports (#1186) ──────────────────────────────── */
+
+typedef enum {
+    PSR4_NOT_APPLICABLE = 0, /* no composer psr-4 prefix covers the import */
+    PSR4_RESOLVED,           /* the class file exists: *out is its File node */
+    PSR4_UNRESOLVED,         /* a prefix covers it but no class file exists */
+} psr4_outcome_t;
+
+/* The File node at exactly `rel_path`, or NULL. Looked up through the name
+ * index (File nodes are named by basename) and matched on the full path, so
+ * a same-named file in another directory never qualifies. */
+static const cbm_gbuf_node_t *psr4_file_node(const cbm_pipeline_ctx_t *ctx, const char *rel_path) {
+    const cbm_gbuf_node_t **hits = NULL;
+    int hit_count = 0;
+    if (cbm_gbuf_find_by_name(ctx->gbuf, path_leaf(rel_path), &hits, &hit_count) != 0 || !hits) {
+        return NULL;
+    }
+    for (int i = 0; i < hit_count; i++) {
+        const cbm_gbuf_node_t *n = hits[i];
+        if (n && n->label && strcmp(n->label, "File") == 0 && n->file_path &&
+            strcmp(n->file_path, rel_path) == 0) {
+            return n;
+        }
+    }
+    return NULL;
+}
+
+/* Resolve a PHP class import `use A\B\C;` the way composer's PSR-4 autoloader
+ * does: for every autoload.psr-4 prefix covering the name, longest first, the
+ * class lives in exactly <prefix-dir>/<rest>.php with sub-namespaces as
+ * subdirectories; the first existing file wins. When a prefix covers the name
+ * but no such file exists the import is UNRESOLVED: it must never fall through
+ * to the namespace bucket, which binds it to whichever file of the namespace
+ * came first. `use function` / `use const` name namespace members, not class
+ * files, so they are not applicable. */
+static psr4_outcome_t resolve_php_psr4_class(const cbm_pipeline_ctx_t *ctx,
+                                             const char *source_file_qn, const CBMImport *imp,
+                                             const cbm_gbuf_node_t **out) {
+    *out = NULL;
+    CBMHashTable *pkgmap = cbm_pipeline_get_pkgmap();
+    if (!pkgmap || imp->kind != CBM_IMPORT_KIND_DEFAULT) {
+        return PSR4_NOT_APPLICABLE;
+    }
+    const char *name = imp->module_path;
+    if (name[0] == '\\') {
+        name++; /* fully qualified `use \App\X;` */
+    }
+    char key[PKGMAP_PATH_BUF];
+    size_t name_len = strlen(name);
+    if (name_len == 0 || name_len >= sizeof(key) || !strchr(name, '\\')) {
+        return PSR4_NOT_APPLICABLE;
+    }
+    bool covered = false;
+    /* Right to left: each '\' ends a candidate prefix, longest first. */
+    for (size_t cut = name_len - SKIP_ONE; cut > 0; cut--) {
+        if (name[cut - SKIP_ONE] != '\\') {
+            continue;
+        }
+        memcpy(key, name, cut);
+        key[cut] = '\0';
+        const char *dir = (const char *)cbm_ht_get(pkgmap, key);
+        if (!dir) {
+            continue;
+        }
+        covered = true;
+        char rel[PKGMAP_PATH_BUF];
+        int w = snprintf(rel, sizeof(rel), "%s%s%s.php", dir, dir[0] ? "/" : "", name + cut);
+        if (w <= 0 || (size_t)w >= sizeof(rel)) {
+            continue;
+        }
+        for (char *c = rel; *c; c++) {
+            if (*c == '\\') {
+                *c = '/';
+            }
+        }
+        const cbm_gbuf_node_t *file = psr4_file_node(ctx, rel);
+        if (file && (!source_file_qn || !file->qualified_name ||
+                     strcmp(file->qualified_name, source_file_qn) != 0)) {
+            *out = file;
+            return PSR4_RESOLVED;
+        }
+    }
+    return covered ? PSR4_UNRESOLVED : PSR4_NOT_APPLICABLE;
+}
+
 const cbm_gbuf_node_t *cbm_pipeline_resolve_import_node(const cbm_pipeline_ctx_t *ctx,
                                                         const char *source_rel,
                                                         const char *source_file_qn,
@@ -2042,6 +2151,18 @@ const cbm_gbuf_node_t *cbm_pipeline_resolve_import_node(const cbm_pipeline_ctx_t
         return header_target;
     }
 
+    /* PHP class imports covered by a composer psr-4 prefix name exactly one
+     * file; when it is absent the import stays unresolved (#1186). */
+    const cbm_gbuf_node_t *psr4_target = NULL;
+    switch (resolve_php_psr4_class(ctx, source_file_qn, imp, &psr4_target)) {
+    case PSR4_RESOLVED:
+        return psr4_target;
+    case PSR4_UNRESOLVED:
+        return NULL;
+    case PSR4_NOT_APPLICABLE:
+        break;
+    }
+
     /* Strategy 1: module-path resolution → existing node (Python/TS/Go).
      * No label filter here: directory-module languages (Go/Java packages)
      * legitimately resolve straight to a Folder node -- that's the intended,

tests/test_edge_imports.c

@@ -1243,6 +1243,194 @@ TEST(ei_php_interface_use) {
     PASS();
 }
 
+/* ═══════════════════════════════════════════════════════════════════════════
+ * PHP PSR-4 — #1186
+ *
+ * With composer.json `autoload.psr-4`, `use App\Models\Agency;` names exactly
+ * one file: <mapped-dir>/Models/Agency.php. The resolver instead fell through
+ * to the namespace bucket and bound every class import of App\Models to the
+ * FIRST file declaring that namespace (User.php), fabricating a hub. These
+ * tests pin the exact target file per local name; a missing class file must
+ * leave the import unresolved rather than land on a sibling.
+ * ═══════════════════════════════════════════════════════════════════════════ */
+
+typedef struct {
+    const char *local_name; /* IMPORTS edge local_name */
+    const char *want_path;  /* expected target file_path; NULL = no edge */
+} EIPhpImportExpect;
+
+/* Find the IMPORTS edge of `importer` whose local_name is `local` and write
+ * its target's file_path into `out` ("" when there is no such edge). */
+static void ei_import_target_path(cbm_store_t *store, const char *project, const char *importer,
+                                  const char *local, char *out, size_t outsz) {
+    out[0] = '\0';
+    int64_t src_id = ei_node_id_for_file_label(store, project, importer, "File");
+    cbm_edge_t *edges = NULL;
+    int n = 0;
+    if (src_id <= 0 ||
+        cbm_store_find_edges_by_source_type(store, src_id, "IMPORTS", &edges, &n) != CBM_STORE_OK) {
+        return;
+    }
+    char needle[256];
+    snprintf(needle, sizeof(needle), "\"local_name\":\"%s\"", local);
+    for (int i = 0; i < n; i++) {
+        if (!edges[i].properties_json || !strstr(edges[i].properties_json, needle)) {
+            continue;
+        }
+        cbm_node_t target;
+        memset(&target, 0, sizeof(target));
+        if (cbm_store_find_node_by_id(store, edges[i].target_id, &target) == CBM_STORE_OK) {
+            snprintf(out, outsz, "%s", target.file_path ? target.file_path : "?");
+            cbm_node_free_fields(&target);
+        }
+        break;
+    }
+    cbm_store_free_edges(edges, n);
+}
+
+/* Index `files` and check every expectation for `importer`. Returns 1 when
+ * all hold; prints each mismatch so a RED names the fabricated target. */
+static int ei_php_imports_match(const EILangFile *files, int nfiles, const char *importer,
+                                const EIPhpImportExpect *want, int nwant) {
+    EILangProj lp;
+    cbm_store_t *store = ei_index_files(&lp, files, nfiles);
+    if (!store) {
+        ei_cleanup(&lp, store);
+        return 0;
+    }
+    int ok = 1;
+    for (int i = 0; i < nwant; i++) {
+        char got[512];
+        ei_import_target_path(store, lp.project, importer, want[i].local_name, got, sizeof(got));
+        const char *expect = want[i].want_path ? want[i].want_path : "";
+        if (strcmp(got, expect) != 0) {
+            fprintf(stderr, "  [IMPORTS %s] %s -> got \"%s\", want \"%s\"\n", importer,
+                    want[i].local_name, got, expect);
+            ok = 0;
+        }
+    }
+    ei_cleanup(&lp, store);
+    return ok;
+}
+
+#define EI_PHP_CLASS(ns, cls) "<?php\nnamespace " ns ";\n\nclass " cls " {\n}\n"
+
+/* Several classes in one namespace directory: each import binds its own file,
+ * not the first file of App\Models. */
+TEST(ei_php_psr4_class_per_file_issue1186) {
+    static const EILangFile f[] = {
+        {"composer.json",
+         "{\"name\":\"acme/app\",\"autoload\":{\"psr-4\":{\"App\\\\\":\"app/\"}}}\n"},
+        {"app/Models/Agency.php", EI_PHP_CLASS("App\\Models", "Agency")},
+        {"app/Models/Client.php", EI_PHP_CLASS("App\\Models", "Client")},
+        {"app/Models/Property.php", EI_PHP_CLASS("App\\Models", "Property")},
+        {"app/Models/User.php", EI_PHP_CLASS("App\\Models", "User")},
+        {"app/Http/Controller.php", "<?php\nnamespace App\\Http;\n\n"
+                                    "use App\\Models\\Property;\nuse App\\Models\\User;\n"
+                                    "use App\\Models\\Client as C;\n\n"
+                                    "class Controller {\n}\n"}};
+    static const EIPhpImportExpect want[] = {
+        {"Property", "app/Models/Property.php"},
+        {"User", "app/Models/User.php"},
+        {"C", "app/Models/Client.php"},
+    };
+    ASSERT_TRUE(ei_php_imports_match(f, 6, "app/Http/Controller.php", want, 3));
+    PASS();
+}
+
+/* Sub-namespaces map to subdirectories of the PSR-4 root, at any depth. */
+TEST(ei_php_psr4_nested_subnamespace_issue1186) {
+    static const EILangFile f[] = {
+        {"composer.json", "{\"autoload\":{\"psr-4\":{\"App\\\\\":\"app/\"}}}\n"},
+        {"app/Models/Billing/Account.php", EI_PHP_CLASS("App\\Models\\Billing", "Account")},
+        {"app/Models/Billing/Invoice.php", EI_PHP_CLASS("App\\Models\\Billing", "Invoice")},
+        {"app/Models/Billing/Tax/Exempt.php", EI_PHP_CLASS("App\\Models\\Billing\\Tax", "Exempt")},
+        {"app/Models/Billing/Tax/Rate.php", EI_PHP_CLASS("App\\Models\\Billing\\Tax", "Rate")},
+        {"app/Jobs/Bill.php", "<?php\nnamespace App\\Jobs;\n\n"
+                              "use App\\Models\\Billing\\Invoice;\n"
+                              "use App\\Models\\Billing\\Tax\\Rate;\n\n"
+                              "class Bill {\n}\n"}};
+    static const EIPhpImportExpect want[] = {
+        {"Invoice", "app/Models/Billing/Invoice.php"},
+        {"Rate", "app/Models/Billing/Tax/Rate.php"},
+    };
+    ASSERT_TRUE(ei_php_imports_match(f, 6, "app/Jobs/Bill.php", want, 2));
+    PASS();
+}
+
+/* Several psr-4 roots, across two composer.json files and both autoload
+ * sections: the longest matching prefix wins (App\Domain\ -> src/Domain/ over
+ * App\ -> app/), a package's own root maps its namespace, and autoload-dev
+ * maps Tests\. The decoy app/Domain/Order.php declares the same namespace and
+ * sorts first. */
+TEST(ei_php_psr4_multiple_roots_longest_prefix_issue1186) {
+    static const EILangFile f[] = {
+        {"composer.json", "{\"autoload\":{\"psr-4\":{\"App\\\\\":\"app/\","
+                          "\"App\\\\Domain\\\\\":\"src/Domain/\"}},"
+                          "\"autoload-dev\":{\"psr-4\":{\"Tests\\\\\":\"tests/\"}}}\n"},
+        {"tests/Support/Assert.php", EI_PHP_CLASS("Tests\\Support", "Assert")},
+        {"tests/Support/Factory.php", EI_PHP_CLASS("Tests\\Support", "Factory")},
+        {"packages/billing/composer.json",
+         "{\"name\":\"acme/billing\",\"autoload\":{\"psr-4\":{\"Billing\\\\\":\"src/\"}}}\n"},
+        {"app/Domain/Order.php", EI_PHP_CLASS("App\\Domain", "Order")},
+        {"src/Domain/Customer.php", EI_PHP_CLASS("App\\Domain", "Customer")},
+        {"src/Domain/Order.php", EI_PHP_CLASS("App\\Domain", "Order")},
+        {"packages/billing/src/Account.php", EI_PHP_CLASS("Billing", "Account")},
+        {"packages/billing/src/Ledger.php", EI_PHP_CLASS("Billing", "Ledger")},
+        {"app/Http/Checkout.php", "<?php\nnamespace App\\Http;\n\n"
+                                  "use App\\Domain\\Order;\nuse Billing\\Ledger;\n"
+                                  "use Tests\\Support\\Assert;\n\n"
+                                  "class Checkout {\n}\n"}};
+    static const EIPhpImportExpect want[] = {
+        {"Order", "src/Domain/Order.php"},
+        {"Ledger", "packages/billing/src/Ledger.php"},
+        {"Assert", "tests/Support/Assert.php"},
+    };
+    ASSERT_TRUE(ei_php_imports_match(f, 10, "app/Http/Checkout.php", want, 3));
+    PASS();
+}
+
+/* Control: `use function` / `use const` name a namespace member, not a class
+ * file, so they must not go through PSR-4 class-file mapping (there is no
+ * app/Helpers/format_money.php); they keep resolving to the declaring file. */
+TEST(ei_php_psr4_use_function_not_class_mapped_issue1186) {
+    static const EILangFile f[] = {
+        {"composer.json", "{\"autoload\":{\"psr-4\":{\"App\\\\\":\"app/\"}}}\n"},
+        {"app/Helpers/money.php", "<?php\nnamespace App\\Helpers;\n\n"
+                                  "const CURRENCY = 'EUR';\n\n"
+                                  "function format_money($x) { return $x; }\n"},
+        {"app/Http/Shop.php", "<?php\nnamespace App\\Http;\n\n"
+                              "use function App\\Helpers\\format_money;\n"
+                              "use const App\\Helpers\\CURRENCY;\n\n"
+                              "class Shop {\n"
+                              "    public function show() { return format_money(CURRENCY); }\n"
+                              "}\n"}};
+    static const EIPhpImportExpect want[] = {
+        {"format_money", "app/Helpers/money.php"},
+        {"CURRENCY", "app/Helpers/money.php"},
+    };
+    ASSERT_TRUE(ei_php_imports_match(f, 3, "app/Http/Shop.php", want, 2));
+    PASS();
+}
+
+/* Control: a PSR-4 class whose file does not exist stays unresolved — it must
+ * never fall back to the first file of the namespace directory. The present
+ * sibling import still resolves. */
+TEST(ei_php_psr4_missing_class_file_unresolved_issue1186) {
+    static const EILangFile f[] = {
+        {"composer.json", "{\"autoload\":{\"psr-4\":{\"App\\\\\":\"app/\"}}}\n"},
+        {"app/Models/User.php", EI_PHP_CLASS("App\\Models", "User")},
+        {"app/Http/Guard.php", "<?php\nnamespace App\\Http;\n\n"
+                               "use App\\Models\\Ghost;\nuse App\\Models\\User;\n\n"
+                               "class Guard {\n}\n"}};
+    static const EIPhpImportExpect want[] = {
+        {"Ghost", NULL},
+        {"User", "app/Models/User.php"},
+    };
+    ASSERT_TRUE(ei_php_imports_match(f, 3, "app/Http/Guard.php", want, 2));
+    PASS();
+}
+
 /* ═══════════════════════════════════════════════════════════════════════════
  * SUITE registration
  * ═══════════════════════════════════════════════════════════════════════════ */
@@ -1326,4 +1514,9 @@ SUITE(edge_imports) {
     RUN_TEST(ei_php_const_use);
     RUN_TEST(ei_php_multiple_use_statements);
     RUN_TEST(ei_php_interface_use);
+    RUN_TEST(ei_php_psr4_class_per_file_issue1186);
+    RUN_TEST(ei_php_psr4_nested_subnamespace_issue1186);
+    RUN_TEST(ei_php_psr4_multiple_roots_longest_prefix_issue1186);
+    RUN_TEST(ei_php_psr4_use_function_not_class_mapped_issue1186);
+    RUN_TEST(ei_php_psr4_missing_class_file_unresolved_issue1186);
 }