Add Dart apis for mathematical functions in moor_ffi

moor/lib/extensions/moor_ffi.dart

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+/// High-level bindings to mathematical functions that are only available in
+/// `moor_ffi`.
+library moor_ffi_functions;
+
+import 'dart:math';
+import 'package:moor/moor.dart';
+
+/// Raises [base] to the power of [exponent].
+///
+/// This function is equivalent to [pow], except that it evaluates to null
+/// instead of `NaN`.
+///
+/// This function is only available when using `moor_ffi`.
+Expression<num> sqlPow(Expression<num> base, Expression<num> exponent) {
+  return FunctionCallExpression('pow', [base, exponent]);
+}
+
+/// Calculates the square root of [value] in sql.
+///
+/// This function is equivalent to [sqrt], except that it returns null instead
+/// of `NaN` for negative values.
+///
+/// This function is only available when using `moor_ffi`.
+Expression<num> sqlSqrt(Expression<num> value) {
+  return FunctionCallExpression('sqrt', [value]);
+}
+
+/// Calculates the sine of [value] in sql.
+///
+/// This function is equivalent to [sin].
+///
+/// This function is only available when using `moor_ffi`.
+Expression<num> sqlSin(Expression<num> value) {
+  return FunctionCallExpression('sin', [value]);
+}
+
+/// Calculates the cosine of [value] in sql.
+///
+/// This function is equivalent to [sin].
+///
+/// This function is only available when using `moor_ffi`.
+Expression<num> sqlCos(Expression<num> value) {
+  return FunctionCallExpression('cos', [value]);
+}
+
+/// Calculates the tangent of [value] in sql.
+///
+/// This function is equivalent to [tan].
+///
+/// This function is only available when using `moor_ffi`.
+Expression<num> sqlTan(Expression<num> value) {
+  return FunctionCallExpression('tan', [value]);
+}
+
+/// Calculates the arc sine of [value] in sql.
+///
+/// This function is equivalent to [asin], except that it evaluates to null
+/// instead of `NaN`.
+///
+/// This function is only available when using `moor_ffi`.
+Expression<num> sqlAsin(Expression<num> value) {
+  return FunctionCallExpression('asin', [value]);
+}
+
+/// Calculates the cosine of [value] in sql.
+///
+/// This function is equivalent to [acos], except that it evaluates to null
+/// instead of `NaN`.
+///
+/// This function is only available when using `moor_ffi`.
+Expression<num> sqlAcos(Expression<num> value) {
+  return FunctionCallExpression('acos', [value]);
+}
+
+/// Calculates the tangent of [value] in sql.
+///
+/// This function is equivalent to [atan], except that it evaluates to null
+/// instead of `NaN`.
+///
+/// This function is only available when using `moor_ffi`.
+Expression<num> sqlAtan(Expression<num> value) {
+  return FunctionCallExpression('atan', [value]);
+}

moor/test/extensions/moor_ffi_functions_test.dart

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+import 'package:moor/extensions/moor_ffi.dart';
+import 'package:moor/src/runtime/query_builder/query_builder.dart';
+import 'package:test/test.dart';
+
+import '../data/utils/expect_generated.dart';
+
+void main() {
+  final a = GeneratedRealColumn('a', null, false);
+  final b = GeneratedRealColumn('b', null, false);
+
+  test('pow', () {
+    expect(sqlPow(a, b), generates('pow(a, b)'));
+  });
+
+  test('sqrt', () => expect(sqlSqrt(a), generates('sqrt(a)')));
+  test('sin', () => expect(sqlSin(a), generates('sin(a)')));
+  test('cos', () => expect(sqlCos(a), generates('cos(a)')));
+  test('tan', () => expect(sqlTan(a), generates('tan(a)')));
+  test('asin', () => expect(sqlAsin(a), generates('asin(a)')));
+  test('acos', () => expect(sqlAcos(a), generates('acos(a)')));
+  test('atan', () => expect(sqlAtan(a), generates('atan(a)')));
+}