ww+selfhost: prepend source dir to import search path

cmd/ww/main.c

@@ -225,13 +225,31 @@ build_one(const char *src, const char *out, const char *extra_includes,
 		else srcdir = libdir;
 	}
 
-	/* Compose the search path: any -I dirs first, then srcdir.
+	/* Compose the search path: source-file's directory first, then any
-	 * locate_import walks them left-to-right. */
+	 * -I dirs, then srcdir. The source-dir lead matches Hare's CWD-first
+	 * convention (its `hare test` is run from the module dir, making CWD
+	 * == module-dir); our wrappers don't cd, so dirname(src) is the
+	 * closest analog. Also matches cc -I. — source-dir wins ties over
+	 * the system path. locate_import walks left-to-right. */
+	char srcd[1024];
+	{
+		const char *slash = strrchr(src, '/');
+		if (slash) {
+			size_t n = (size_t)(slash - src);
+			if (n >= sizeof srcd) n = sizeof srcd - 1;
+			memcpy(srcd, src, n);
+			srcd[n] = '\0';
+		} else {
+			srcd[0] = '.';
+			srcd[1] = '\0';
+		}
+	}
 	static char searchpath[4096];
 	if (extra_includes && extra_includes[0])
-		snprintf(searchpath, sizeof searchpath, "%s:%s", extra_includes, srcdir);
+		snprintf(searchpath, sizeof searchpath, "%s:%s:%s",
+		    srcd, extra_includes, srcdir);
 	else
-		snprintf(searchpath, sizeof searchpath, "%s", srcdir);
+		snprintf(searchpath, sizeof searchpath, "%s:%s", srcd, srcdir);
 	srcdir = searchpath;
 
 	/* Strip extension to derive a stem; e.g. /tmp/foo.ww → /tmp/foo */

selfhost/cmd/ww/main.combined.ww

@@ -862,10 +862,40 @@ fn buildone(selfdir: *u8, src: *u8, out: *u8, incs: *u8, lf: *lflags) i32 = {
 		cstrseal(dotdotlib, off);
 	};
 
-	// Compose searchpath: incs + ':' + dotdotlib (or just dotdotlib).
+	// Compute the source-file's directory: bytes of `src` up to the
-	let searchpath: *u8 = os.alloc(PATH_MAX * 2u64): *u8;
+	// last '/'. If `src` has no '/', use ".". Hare's CWD-first
+	// convention assumes you're running from the module dir; our
+	// wrappers don't cd, so dirname(src) stands in as the closest
+	// analog. Source-dir wins ties over the system path (cc -I.).
+	let srcd: *u8 = os.alloc(PATH_MAX): *u8;
 	{
-		let off: u64 = 0u64;
+		let slen: u64 = cstrlen(src);
+		let last: u64 = slen;
+		let found: bool = false;
+		let i: u64 = slen;
+		for (i > 0u64) {
+			i -= 1u64;
+			if (src[i] == 47u8) {	// '/'
+				last = i;
+				found = true;
+				i = 0u64;
+			};
+		};
+		if (found) {
+			let k: u64 = 0u64;
+			for (k < last) { srcd[k] = src[k]; k += 1u64; };
+			srcd[last] = 0u8;
+		} else {
+			srcd[0] = 46u8;		// '.'
+			srcd[1] = 0u8;
+		};
+	};
+
+	// Compose searchpath: srcd + ':' + incs + ':' + dotdotlib.
+	let searchpath: *u8 = os.alloc(PATH_MAX * 3u64): *u8;
+	{
+		let off: u64 = cstrinto(searchpath, 0u64, srcd);
+		off = byteinto(searchpath, off, 58u8);	// ':'
 		if (incs[0u64] != 0u8) {
 			off = cstrinto(searchpath, off, incs);
 			off = byteinto(searchpath, off, 58u8);	// ':'

selfhost/cmd/ww/main.ww

@@ -508,10 +508,40 @@ fn buildone(selfdir: *u8, src: *u8, out: *u8, incs: *u8, lf: *lflags) i32 = {
 		cstrseal(dotdotlib, off);
 	};
 
-	// Compose searchpath: incs + ':' + dotdotlib (or just dotdotlib).
+	// Compute the source-file's directory: bytes of `src` up to the
-	let searchpath: *u8 = os.alloc(PATH_MAX * 2u64): *u8;
+	// last '/'. If `src` has no '/', use ".". Hare's CWD-first
+	// convention assumes you're running from the module dir; our
+	// wrappers don't cd, so dirname(src) stands in as the closest
+	// analog. Source-dir wins ties over the system path (cc -I.).
+	let srcd: *u8 = os.alloc(PATH_MAX): *u8;
 	{
-		let off: u64 = 0u64;
+		let slen: u64 = cstrlen(src);
+		let last: u64 = slen;
+		let found: bool = false;
+		let i: u64 = slen;
+		for (i > 0u64) {
+			i -= 1u64;
+			if (src[i] == 47u8) {	// '/'
+				last = i;
+				found = true;
+				i = 0u64;
+			};
+		};
+		if (found) {
+			let k: u64 = 0u64;
+			for (k < last) { srcd[k] = src[k]; k += 1u64; };
+			srcd[last] = 0u8;
+		} else {
+			srcd[0] = 46u8;		// '.'
+			srcd[1] = 0u8;
+		};
+	};
+
+	// Compose searchpath: srcd + ':' + incs + ':' + dotdotlib.
+	let searchpath: *u8 = os.alloc(PATH_MAX * 3u64): *u8;
+	{
+		let off: u64 = cstrinto(searchpath, 0u64, srcd);
+		off = byteinto(searchpath, off, 58u8);	// ':'
 		if (incs[0u64] != 0u8) {
 			off = cstrinto(searchpath, off, incs);
 			off = byteinto(searchpath, off, 58u8);	// ':'