Add support for long tons

src/conversions.rs

@@ -69,6 +69,11 @@ fn get_conversion(unit: NonMetric) -> Conversion {
 			from: pound_from,
 			to: MetricQuantity { amount: 2000.0 * pound_to, unit: Metric::Gram },
 		},
+		NonMetric::LongTon => Conversion {
+			offset: 0.0,
+			from: pound_from,
+			to: MetricQuantity { amount: 2240.0 * pound_to, unit: Metric::Gram },
+		},
 		// Temperature
 		NonMetric::Fahrenheit => Conversion {
 			offset: 32.0,
@@ -190,6 +195,7 @@ mod test {
 			Test(NonMetric::Pound, 453.59237),
 			Test(NonMetric::Stone, 6350.29318),
 			Test(NonMetric::ShortTon, 907184.74),
+			Test(NonMetric::LongTon, 1016046.9088),
 		];
 		run_tests(&tests, Metric::Gram);
 	}

src/lib.rs

@@ -78,6 +78,7 @@ fn unit_to_name(unit: NonMetric) -> &'static str {
 		NonMetric::Pound => "pounds",
 		NonMetric::Stone => "stones",
 		NonMetric::ShortTon => "short tons",
+		NonMetric::LongTon => "long tons",
 		// Temperature
 		NonMetric::Fahrenheit => "degrees Fahrenheit",
 		// Area
@@ -131,6 +132,7 @@ mod test {
 		assert_eq!(run("1 lb"), Ok("453.6 g".to_string()));
 		assert_eq!(run("1 st"), Ok("6.35 kg".to_string()));
 		assert_eq!(run("1 short ton"), Ok("907.2 kg".to_string()));
+		assert_eq!(run("1 long ton"), Ok("1 016 kg".to_string()));
 		// Temperature
 		assert_eq!(run("-40 °F"), Ok("-40 °C".to_string()));
 		assert_eq!(run("0 °F"), Ok("-17.78 °C".to_string()));

src/parse.rs

@@ -105,6 +105,13 @@ fn parse_unit(input: String) -> Result<NonMetric, ParseError> {
 		"us ton" => Ok(NonMetric::ShortTon),
 		"us tons" => Ok(NonMetric::ShortTon),
 
+		"long ton" => Ok(NonMetric::LongTon),
+		"long tons" => Ok(NonMetric::LongTon),
+		"imperial ton" => Ok(NonMetric::LongTon),
+		"imperial tons" => Ok(NonMetric::LongTon),
+		"imp ton" => Ok(NonMetric::LongTon),
+		"imp tons" => Ok(NonMetric::LongTon),
+
 		// Temperature
 		"degree Fahrenheit" => Ok(NonMetric::Fahrenheit),
 		"degrees Fahrenheit" => Ok(NonMetric::Fahrenheit),
@@ -479,6 +486,15 @@ mod test {
 			"us tons",
 		]);
 
+		test_units(NonMetric::LongTon, &[
+			"long ton",
+			"long tons",
+			"imperial ton",
+			"imperial tons",
+			"imp ton",
+			"imp tons",
+		]);
+
 		// Temperature
 		test_units(NonMetric::Fahrenheit, &[
 			"degree Fahrenheit",

src/units.rs

@@ -20,6 +20,7 @@ pub enum NonMetric {
 	Pound,
 	Stone,
 	ShortTon,
+	LongTon,
 	// Temperature
 	Fahrenheit,
 	// Area