Make import keyword change working directory during external compilation

src/classes/file.c

@@ -110,6 +110,19 @@ void file_setworkingdirectory(const char *path) {
     }
 }
 
+/** Gets the global current working directory (relative to the filing systems cwd.
+ * @param[out] path - path to working directory. */
+void file_getworkingdirectory(varray_char *path)
+{
+    if (workingdir.count>0) {
+        for (unsigned int i=0; i<workingdir.count && workingdir.data[i]!='\0'; i++) {
+            varray_charwrite(path, workingdir.data[i]);
+        }
+        varray_charwrite(path, MORPHO_DIRSEPARATOR);
+    }
+    varray_charwrite(path, '\0');
+}
+
 /** Gets the relative path for a given file */
 void file_relativepath(const char *fname, varray_char *name) {
     /* Check the fname passed isn't a global file reference (i.e. starts with / or ~) */
@@ -119,7 +132,7 @@ void file_relativepath(const char *fname, varray_char *name) {
             for (unsigned int i=0; i<workingdir.count && workingdir.data[i]!='\0'; i++) {
                 varray_charwrite(name, workingdir.data[i]);
             }
-            varray_charwrite(name, '/');
+            varray_charwrite(name, MORPHO_DIRSEPARATOR);
         }
     }
     varray_charadd(name, (char *) fname, (int) strlen(fname));

src/classes/file.h

@@ -99,7 +99,8 @@ typedef struct {
  * ------------------------------------------------------- */
 
 bool file_getsize(FILE *f, size_t *s);
-void file_setworkingdirectory(const char *script);
+void file_setworkingdirectory(const char *path);
+void file_getworkingdirectory(varray_char *path);
 FILE *file_openrelative(const char *fname, const char *mode);
 int file_readlineintovarray(FILE *f, varray_char *string);
 bool file_readintovarray(FILE *f, varray_char *string);

src/core/compile.c

@@ -4805,6 +4805,16 @@ static codeinfo compiler_import(compiler *c, syntaxtreenode *node, registerindx
                 goto compiler_import_cleanup;
             }
 
+            /* Change working directory to new file for duration of import compilation */
+            varray_char wrkdir;
+            varray_charinit(&wrkdir);
+            file_getworkingdirectory(&wrkdir);
+            varray_char fpath;
+            varray_charinit(&fpath);
+            varray_charadd(&fpath, wrkdir.data, wrkdir.count-1);
+            varray_charadd(&fpath, fname, (int) strlen(fname));
+            file_setworkingdirectory(fpath.data);
+
             /* Remember the initial position of the code */
             start=c->out->code.count;
 
@@ -4841,6 +4851,11 @@ static codeinfo compiler_import(compiler *c, syntaxtreenode *node, registerindx
             debugannotation_setmodule(&c->out->annotations, compiler_getmodule(c));
 
             end=c->out->code.count;
+
+            /* Restore old working directory */
+            file_setworkingdirectory(wrkdir.data);
+            varray_charclear(&wrkdir);
+            varray_charclear(&fpath);
 
             compiler_clear(&cc);
             varray_charclear(&src);

test/import/relative_directory.morpho

@@ -0,0 +1,5 @@
+import "relative_directory/target.m"
+// expect: Successfully imported target
+
+folderfn("Hello world")
+// expect: Hello world

test/import/relative_directory/inner_target.m

@@ -0,0 +1,3 @@
+fn folderfn(message) {
+    print message
+}

test/import/relative_directory/target.m

@@ -0,0 +1,3 @@
+import "inner_target.m"
+
+print "Successfully imported target"