[varint] Add LEB128 decoding + tests

Also make tests in general less spammy: Don't print [PASS] for each successful test, only report failures and progress.

tests/core/odin/test_parser.odin

@@ -10,34 +10,31 @@ TEST_count := 0
 TEST_fail  := 0
 
 when ODIN_TEST {
-    expect  :: testing.expect
-    log     :: testing.log
+	expect  :: testing.expect
+	log     :: testing.log
 } else {
-    expect  :: proc(t: ^testing.T, condition: bool, message: string, loc := #caller_location) {
-        fmt.printf("[%v] ", loc)
-        TEST_count += 1
-        if !condition {
-            TEST_fail += 1
-            fmt.println(message)
-            return
-        }
-        fmt.println(" PASS")
-    }
-    log     :: proc(t: ^testing.T, v: any, loc := #caller_location) {
-        fmt.printf("[%v] ", loc)
-        fmt.printf("log: %v\n", v)
-    }
+	expect  :: proc(t: ^testing.T, condition: bool, message: string, loc := #caller_location) {
+		TEST_count += 1
+		if !condition {
+			TEST_fail += 1
+			fmt.printf("[%v] %v\n", loc, message)
+			return
+		}
+	}
+	log     :: proc(t: ^testing.T, v: any, loc := #caller_location) {
+		fmt.printf("[%v] ", loc)
+		fmt.printf("log: %v\n", v)
+	}
 }
 
-
 main :: proc() {
-    t := testing.T{}
-    test_parse_demo(&t)
+	t := testing.T{}
+	test_parse_demo(&t)
 
-    fmt.printf("%v/%v tests successful.\n", TEST_count - TEST_fail, TEST_count)
-    if TEST_fail > 0 {
-        os.exit(1)
-    }
+	fmt.printf("%v/%v tests successful.\n", TEST_count - TEST_fail, TEST_count)
+	if TEST_fail > 0 {
+		os.exit(1)
+	}
 }
 
 
@@ -50,4 +47,4 @@ test_parse_demo :: proc(t: ^testing.T) {
 	for key, value in pkg.files {
 		expect(t, value.syntax_error_count == 0, fmt.tprintf("%v should contain zero errors", key))
 	}
-}
+}