Add TomlTableWithSource.getLongOrNone()

1 files changed, 21 insertions, 0 deletions

diff --git a/src/main/java/org/shedlang/compiler/config/toml/TomlTableWithSource.java b/src/main/java/org/shedlang/compiler/config/toml/TomlTableWithSource.java
index 725d510a..d6ac3ba8 100644
--- a/src/main/java/org/shedlang/compiler/config/toml/TomlTableWithSource.java
+++ b/src/main/java/org/shedlang/compiler/config/toml/TomlTableWithSource.java
@@ -12,6 +12,7 @@ import org.tomlj.TomlTable;
 import java.text.MessageFormat;
 import java.util.List;
 import java.util.Optional;
+import java.util.OptionalLong;
 import java.util.stream.IntStream;
 
 public record TomlTableWithSource(
@@ -149,6 +150,26 @@ public record TomlTableWithSource(
         );
     }
 
+    public OptionalLong getLongOrNone(String key) {
+        var value = table.get(key);
+        var valuePosition = table.inputPositionOf(key);
+
+        if (value == null) {
+            return OptionalLong.empty();
+        }
+
+        if (value instanceof Long valueLong) {
+            return OptionalLong.of(valueLong);
+        }
+
+        throw new UnexpectedTypeConfigError(
+            path.plusKey(key),
+            "a long",
+            value.getClass(),
+            TomlSource.sourceAtTomlPosition(fullSource, valuePosition)
+        );
+    }
+
     public long getLong(String key) {
         var value = table.get(key);
         var valuePosition = table.inputPositionOf(key);