Add support for square feet

src/conversions.rs

@@ -70,6 +70,11 @@ fn get_conversion(unit: NonMetric) -> Conversion {
 			from: inch_from * inch_from,
 			to: MetricQuantity { amount: inch_to * inch_to, unit: Metric::SquareMetre },
 		},
+		NonMetric::SquareFoot => Conversion {
+			offset: 0.0,
+			from: inch_from * inch_from,
+			to: MetricQuantity { amount: 12.0 * inch_to * 12.0 * inch_to, unit: Metric::SquareMetre },
+		},
 	}
 }
 
@@ -122,6 +127,7 @@ mod test {
 	fn area() {
 		let tests = [
 			Test(NonMetric::SquareInch, 0.00064516),
+			Test(NonMetric::SquareFoot, 0.09290304),
 		];
 		run_tests(&tests, Metric::SquareMetre);
 	}

src/lib.rs

@@ -74,6 +74,7 @@ fn unit_to_name(unit: NonMetric) -> &'static str {
 		NonMetric::Fahrenheit => "degrees Fahrenheit",
 		// Area
 		NonMetric::SquareInch => "square inches",
+		NonMetric::SquareFoot => "square feet",
 	}
 }
 
@@ -108,5 +109,6 @@ mod test {
 		assert_eq!(run("32 °F"), Ok("0 °C".to_string()));
 		// Area
 		assert_eq!(run("1 in²"), Ok("6.452 cm²".to_string()));
+		assert_eq!(run("1 ft²"), Ok("929 cm²".to_string()));
 	}
 }

src/parse.rs

@@ -106,6 +106,10 @@ fn parse_unit(input: String) -> Result<NonMetric, ParseError> {
 		"inches²" => Ok(NonMetric::SquareInch),
 		"in²" => Ok(NonMetric::SquareInch),
 
+		"foot²" => Ok(NonMetric::SquareFoot),
+		"feet²" => Ok(NonMetric::SquareFoot),
+		"ft²" => Ok(NonMetric::SquareFoot),
+
 		_ => Err(ParseError::UnknownUnit(input)),
 	}
 }
@@ -259,6 +263,10 @@ mod test {
 		assert_eq!(parse_unit("inches²".to_string()), Ok(NonMetric::SquareInch));
 		assert_eq!(parse_unit("in²".to_string()), Ok(NonMetric::SquareInch));
 
+		assert_eq!(parse_unit("foot²".to_string()), Ok(NonMetric::SquareFoot));
+		assert_eq!(parse_unit("feet²".to_string()), Ok(NonMetric::SquareFoot));
+		assert_eq!(parse_unit("ft²".to_string()), Ok(NonMetric::SquareFoot));
+
 		// Unknown unit
 		assert_eq!(parse_unit("hutenosa".to_string()), Err(ParseError::UnknownUnit("hutenosa".to_string())));
 	}

src/units.rs

@@ -21,6 +21,7 @@ pub enum NonMetric {
 	Fahrenheit,
 	// Area
 	SquareInch,
+	SquareFoot,
 }
 
 #[derive(Clone, Copy, Debug, PartialEq)]