lib: introduce three new functions call(), loadstring() and loadfile()

Introduce new functions dealing with on-the-fly compilation of code and
execution of functions with different global scope.

The `loadstring()` and `loadfile()` functions will compile the given
ucode source string or ucode file path respectively and return the entry
function of the resulting program.

An optional dictionary specifying parse options may be given as second
argument.

Both functions return `null` on invalid arguments and throw an exception
in case of compilation errors.

The `call()` function allows invoking a given function value with a
different `this` context and/or a different global environment.

Finally refactor the existing `uc_require_ucode()` implementation to
reuse the new `uc_loadfile()` and `uc_call()` implementations and adjust
as well as simplify affected testcases.

Signed-off-by: Jo-Philipp Wich <jo@mein.io>

1 files changed, 11 insertions, 23 deletions

diff --git a/tests/custom/03_stdlib/29_require b/tests/custom/03_stdlib/29_require
index 4fb4216..a81edb4 100644
--- a/tests/custom/03_stdlib/29_require
+++ b/tests/custom/03_stdlib/29_require
@@ -119,20 +119,9 @@ A compilation error in the module triggers an exception.
 
 -- Testcase --
 {%
-	try {
-		push(REQUIRE_SEARCH_PATH, TESTFILES_PATH + '/*.uc');
+	push(REQUIRE_SEARCH_PATH, TESTFILES_PATH + '/*.uc');
 
-		require("require.test.broken");
-	}
-	catch (e) {
-		// Catch and rethrow exception with modified message to
-		// ensure stable test output.
-		e.message = replace(e.message,
-			/(compile module '.+require\/test\/broken\.uc')/,
-			"compile module '.../require/test/broken.uc'");
-
-		die(e);
-	}
+	require("require.test.broken");
 %}
 -- End --
 
@@ -142,19 +131,18 @@ return {
 -- End --
 
 -- Expect stderr --
-Unable to compile module '.../require/test/broken.uc':
-Syntax error: Expecting label
-In line 2, byte 10:
-
- `return {`
-          ^-- Near here
-
+Runtime error: Unable to compile source file './files/require/test/broken.uc':
 
+  | Syntax error: Expecting label
+  | In line 2, byte 10:
+  |
+  |  `return {`
+  |           ^-- Near here
 
-In line 14, byte 8:
+In line 4, byte 31:
 
- `        die(e);`
-  Near here ---^
+ `    require("require.test.broken");`
+  Near here -----------------------^
 
 
 -- End --