Fix import macro to not coerce everything to string.

CHANGELOG.md

@@ -2,6 +2,8 @@
 All notable changes to this project will be documented in this file.
 
 ## Unreleased - ???
+- Add `:n` flag to `file/open` to raise an error if file cannot be opened.
+- Fix import macro to not try and coerce everything to a string.
 - Allow passing a second argument to `disasm`.
 - Add `cancel`. Resumes a fiber but makes it immediately error at the yield point.
 - Allow multi-line paste into built in repl.

src/boot/boot.janet

@@ -2475,7 +2475,8 @@
   to be called. Dynamic bindings will NOT be imported. Use :fresh to bypass the
   module cache."
   [path & args]
-  (def argm (map |(if (keyword? $) $ (string $)) args))
+  (def ps (partition 2 args))
+  (def argm (mapcat (fn [[k v]] [k (if (= k :as) (string v) v)]) ps))
   (tuple import* (string path) ;argm))
 
 (defmacro use

src/core/io.c

@@ -56,8 +56,8 @@ static int32_t checkflags(const uint8_t *str) {
     int32_t flags = 0;
     int32_t i;
     int32_t len = janet_string_length(str);
-    if (!len || len > 3)
-        janet_panic("file mode must have a length between 1 and 3");
+    if (!len || len > 10)
+        janet_panic("file mode must have a length between 1 and 10");
     switch (*str) {
         default:
             janet_panicf("invalid flag %c, expected w, a, or r", *str);
@@ -75,7 +75,7 @@ static int32_t checkflags(const uint8_t *str) {
     for (i = 1; i < len; i++) {
         switch (str[i]) {
             default:
-                janet_panicf("invalid flag %c, expected + or b", str[i]);
+                janet_panicf("invalid flag %c, expected +, b, or n", str[i]);
                 break;
             case '+':
                 if (flags & JANET_FILE_UPDATE) return -1;
@@ -85,6 +85,10 @@ static int32_t checkflags(const uint8_t *str) {
                 if (flags & JANET_FILE_BINARY) return -1;
                 flags |= JANET_FILE_BINARY;
                 break;
+            case 'n':
+                if (flags & JANET_FILE_NONIL) return -1;
+                flags |= JANET_FILE_NONIL;
+                break;
         }
     }
     return flags;
@@ -112,11 +116,11 @@ static Janet cfun_io_popen(int32_t argc, Janet *argv) {
     int32_t flags;
     if (argc == 2) {
         fmode = janet_getkeyword(argv, 1);
-        if (janet_string_length(fmode) != 1 ||
-                !(fmode[0] == 'r' || fmode[0] == 'w')) {
-            janet_panicf("invalid file mode :%S, expected :r or :w", fmode);
+        flags = JANET_FILE_PIPED | checkflags(fmode);
+        if (flags & (JANET_FILE_UPDATE | JANET_FILE_BINARY | JANET_FILE_APPEND)) {
+            janet_panicf("invalid popen file mode :%S, expected :r or :w", fmode);
         }
-        flags = JANET_FILE_PIPED | (fmode[0] == 'r' ? JANET_FILE_READ : JANET_FILE_WRITE);
+        fmode = (const uint8_t *)((fmode[0] == 'r') ? "r" : "w");
     } else {
         fmode = (const uint8_t *)"r";
         flags = JANET_FILE_PIPED | JANET_FILE_READ;
@@ -126,6 +130,8 @@ static Janet cfun_io_popen(int32_t argc, Janet *argv) {
 #endif
     FILE *f = popen((const char *)fname, (const char *)fmode);
     if (!f) {
+        if (flags & JANET_FILE_NONIL)
+            janet_panicf("failed to popen %s: %s", fname, strerror(errno));
         return janet_wrap_nil();
     }
     return janet_makefile(f, flags);
@@ -155,7 +161,9 @@ static Janet cfun_io_fopen(int32_t argc, Janet *argv) {
         flags = JANET_FILE_READ;
     }
     FILE *f = fopen((const char *)fname, (const char *)fmode);
-    return f ? janet_makefile(f, flags) : janet_wrap_nil();
+    return f ? janet_makefile(f, flags)
+        : (flags & JANET_FILE_NONIL) ? (janet_panicf("failed to open file %s: %s", fname, strerror(errno)), janet_wrap_nil())
+        : janet_wrap_nil();
 }
 
 /* Read up to n bytes into buffer. */
@@ -720,7 +728,8 @@ static const JanetReg io_cfuns[] = {
              "\tw - allow writing to the file\n"
              "\ta - append to the file\n"
              "\tb - open the file in binary mode (rather than text mode)\n"
-             "\t+ - append to the file instead of overwriting it")
+             "\t+ - append to the file instead of overwriting it\n"
+             "\tn - error if the file cannot be opened instead of returning nil")
     },
     {
         "file/close", cfun_io_fclose,

src/include/janet.h

@@ -1540,6 +1540,7 @@ extern JANET_API const JanetAbstractType janet_file_type;
 #define JANET_FILE_BINARY 64
 #define JANET_FILE_SERIALIZABLE 128
 #define JANET_FILE_PIPED 256
+#define JANET_FILE_NONIL 512
 
 JANET_API Janet janet_makefile(FILE *f, int32_t flags);
 JANET_API FILE *janet_getfile(const Janet *argv, int32_t n, int32_t *flags);

test/suite0010.janet

@@ -57,4 +57,8 @@
 (assert (= nil (curenv 1000000)) "curenv 3")
 (assert (= root-env (curenv 1)) "curenv 4")
 
+# Import macro test
+(assert-no-error "import macro 1" (macex '(import a :as b :fresh maybe)))
+(assert (deep= ~(,import* "a" :as "b" :fresh maybe) (macex '(import a :as b :fresh maybe))) "import macro 2")
+
 (end-suite)