diff --git a/base/src/expressions/lexer/test/test_common.rs b/base/src/expressions/lexer/test/test_common.rs
index a3884ee..4a46e03 100644
--- a/base/src/expressions/lexer/test/test_common.rs
+++ b/base/src/expressions/lexer/test/test_common.rs
@@ -4,7 +4,7 @@ use crate::language::get_language;
 use crate::locale::get_locale;
 
 use crate::expressions::{
-    lexer::{Lexer, LexerMode},
+    lexer::{Lexer, LexerError, LexerMode},
     token::TokenType::*,
     token::{Error, OpCompare, OpProduct, OpSum},
     types::ParsedReference,
@@ -411,6 +411,20 @@ fn test_name_r1c1p() {
     assert_eq!(lx.next_token(), EOF);
 }
 
+#[test]
+fn test_reference_r1c1_error() {
+    let mut lx = new_lexer("$A$4", false);
+    lx.mode = LexerMode::R1C1;
+    assert_eq!(
+        lx.next_token(),
+        Illegal(LexerError {
+            position: 1,
+            message: "Cannot parse A1 reference in R1C1 mode".to_string(),
+        })
+    );
+    assert_eq!(lx.next_token(), EOF);
+}
+
 #[test]
 fn test_name_wrong_ref() {
     let mut lx = new_lexer("Sheet1!2", false);
@@ -629,6 +643,22 @@ fn test_ampersand() {
     assert_eq!(lx.next_token(), EOF);
 }
 
+#[test]
+fn test_comma() {
+    // Used for testing locales where the comma is not a decimal separator
+    let mut lx = new_lexer("12,34", false);
+    assert_eq!(lx.next_token(), Number(12.0));
+    assert_eq!(lx.next_token(), Comma);
+    assert_eq!(lx.next_token(), Number(34.0));
+    assert_eq!(lx.next_token(), EOF);
+
+    // Used for testing locales where the comma is the decimal separator
+    let mut lx = new_lexer("12,34", false);
+    lx.locale.numbers.symbols.decimal = ",".to_string();
+    assert_eq!(lx.next_token(), Number(12.34));
+    assert_eq!(lx.next_token(), EOF);
+}
+
 #[test]
 fn test_semicolon() {
     let mut lx = new_lexer("FALSE;", false);
diff --git a/base/src/expressions/lexer/test/test_ranges.rs b/base/src/expressions/lexer/test/test_ranges.rs
index 628a878..df7b4c4 100644
--- a/base/src/expressions/lexer/test/test_ranges.rs
+++ b/base/src/expressions/lexer/test/test_ranges.rs
@@ -112,6 +112,39 @@ fn test_range_with_sheet_with_space() {
     assert_eq!(lx.next_token(), EOF);
 }
 
+#[test]
+fn test_range_error() {
+    let mut lx = new_lexer("'Sheet 1'!3.4:5");
+    assert_eq!(
+        lx.next_token(),
+        Illegal(LexerError {
+            position: 10,
+            message: "Expecting reference in range".to_string(),
+        })
+    );
+    assert_eq!(lx.next_token(), EOF);
+
+    let mut lx = new_lexer("'Sheet 1'!3:A2");
+    assert_eq!(
+        lx.next_token(),
+        Illegal(LexerError {
+            position: 14,
+            message: "Error parsing Range".to_string()
+        })
+    );
+    assert_eq!(lx.next_token(), EOF);
+
+    let mut lx = new_lexer("'Sheet 1'!3:");
+    assert_eq!(
+        lx.next_token(),
+        Illegal(LexerError {
+            position: 12,
+            message: "Error parsing Range".to_string()
+        })
+    );
+    assert_eq!(lx.next_token(), EOF);
+}
+
 #[test]
 fn test_range_column() {
     let mut lx = new_lexer("C:D");
diff --git a/base/src/expressions/test.rs b/base/src/expressions/test.rs
index 2c61aac..6c58c96 100644
--- a/base/src/expressions/test.rs
+++ b/base/src/expressions/test.rs
@@ -10,6 +10,11 @@ fn test_error_codes() {
         Error::NA,
         Error::NUM,
         Error::ERROR,
+        Error::NIMPL,
+        Error::SPILL,
+        Error::CALC,
+        Error::CIRC,
+        Error::NULL
     ];
     for (i, error) in errors.iter().enumerate() {
         let s = format!("{}", error);