treewide: rewrite ucode interpreter

Replace the former AST walking interpreter implementation with a single pass
bytecode compiler and a corresponding virtual machine.

The rewrite lays the groundwork for a couple of improvements with will be
subsequently implemented:

 - Ability to precompile ucode sources into binary byte code
 - Strippable debug information
 - Reduced runtime memory usage

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

1 files changed, 37 insertions, 11 deletions

diff --git a/tests/02_runtime/04_switch_case b/tests/02_runtime/04_switch_case
index 0de87dc..4c1fc57 100644
--- a/tests/02_runtime/04_switch_case
+++ b/tests/02_runtime/04_switch_case
@@ -84,7 +84,26 @@ default
 -- End --
 
 
-4. Ensure that duplicate default cases emit a syntax
+4. Ensure that a single default case matches.
+
+-- Expect stdout --
+default
+default
+-- End --
+
+-- Testcase --
+{%
+	for (n in [1, 3]) {
+		switch (n) {
+		default:
+			print("default\n");
+		}
+	}
+%}
+-- End --
+
+
+5. Ensure that duplicate default cases emit a syntax
    error during parsing.
 
 -- Expect stderr --
@@ -95,6 +114,13 @@ In line 6, byte 3:
           ^-- Near here
 
 
+Syntax error: Expecting expression
+In line 8, byte 2:
+
+ `    }`
+      ^-- Near here
+
+
 -- End --
 
 -- Testcase --
@@ -110,7 +136,7 @@ In line 6, byte 3:
 -- End --
 
 
-5. Ensure that case values use strict comparison.
+6. Ensure that case values use strict comparison.
 
 -- Expect stdout --
 b
@@ -142,7 +168,7 @@ b
 -- End --
 
 
-6. Ensure that case values may be complex expressions.
+7. Ensure that case values may be complex expressions.
 
 -- Expect stdout --
 2, 3, 1
@@ -159,7 +185,7 @@ b
 -- End --
 
 
-7. Ensure that empty switch statements are accepted by the
+8. Ensure that empty switch statements are accepted by the
    parser and that the test expression is evaluated.
 
 -- Expect stdout --
@@ -179,7 +205,7 @@ true
 -- End --
 
 
-8. Ensure that `return` breaks out of switch statements.
+9. Ensure that `return` breaks out of switch statements.
 
 -- Expect stdout --
 one
@@ -207,7 +233,7 @@ two
 -- End --
 
 
-9. Ensure that `continue` breaks out of switch statements.
+10. Ensure that `continue` breaks out of switch statements.
 
 -- Expect stdout --
 one
@@ -234,7 +260,7 @@ two
 -- End --
 
 
-10. Ensure that exceptions break out of switch statements.
+11. Ensure that exceptions break out of switch statements.
 
 -- Expect stdout --
 one
@@ -242,11 +268,11 @@ one
 
 -- Expect stderr --
 Died
-In test(), line 6, byte 7:
-  called from anonymous function ([stdin]:17:12)
+In test(), line 6, byte 8:
+  called from anonymous function ([stdin]:17:14)
 
  `            die();`
-  Near here -----^
+  Near here ------^
 
 
 -- End --
@@ -273,7 +299,7 @@ In test(), line 6, byte 7:
 -- End --
 
 
-11. Ensure that consecutive cases values are properly handled.
+12. Ensure that consecutive cases values are properly handled.
 
 -- Expect stdout --
 three and four