Merge pull request #1219 from ypyf/math

Add math.gcd

tests/snippets/math_module.py

@@ -87,3 +87,13 @@ assert math.frexp(1.5) == (0.75, 1)
 assert math.frexp(float('inf')) == (float('inf'), 0)
 assert str(math.frexp(float('nan'))) == str((float('nan'), 0))
 assert_raises(TypeError, lambda: math.frexp(None))
+
+assert math.gcd(0, 0) == 0
+assert math.gcd(1, 0) == 1
+assert math.gcd(0, 1) == 1
+assert math.gcd(1, 1) == 1
+assert math.gcd(-1, 1) == 1
+assert math.gcd(1, -1) == 1
+assert math.gcd(-1, -1) == 1
+assert math.gcd(125, -255) == 5
+assert_raises(TypeError, lambda: math.gcd(1.1, 2))

vm/src/stdlib/math.rs

@@ -7,6 +7,7 @@ use statrs::function::erf::{erf, erfc};
 use statrs::function::gamma::{gamma, ln_gamma};
 
 use crate::function::PyFuncArgs;
+use crate::obj::objint::PyIntRef;
 use crate::obj::{objfloat, objtype};
 use crate::pyobject::{PyObjectRef, PyResult, TypeProtocol};
 use crate::vm::VirtualMachine;
@@ -225,6 +226,11 @@ fn math_frexp(value: PyObjectRef, vm: &VirtualMachine) -> PyResult {
     )
 }
 
+fn math_gcd(a: PyIntRef, b: PyIntRef, vm: &VirtualMachine) -> PyResult {
+    use num_integer::Integer;
+    Ok(vm.new_int(a.as_bigint().gcd(b.as_bigint())))
+}
+
 pub fn make_module(vm: &VirtualMachine) -> PyObjectRef {
     let ctx = &vm.ctx;
 
@@ -279,6 +285,9 @@ pub fn make_module(vm: &VirtualMachine) -> PyObjectRef {
         "ceil" => ctx.new_rustfunc(math_ceil),
         "floor" => ctx.new_rustfunc(math_floor),
 
+        // Gcd function
+        "gcd" => ctx.new_rustfunc(math_gcd),
+
         // Constants:
         "pi" => ctx.new_float(std::f64::consts::PI), // 3.14159...
         "e" => ctx.new_float(std::f64::consts::E), // 2.71..