github.hscsec.cn/u-root/u-root@v7.0.0+incompatible/pkg/pogosh/arithmetic_test.go (about)

     1  // Copyright 2020 the u-root Authors. All rights reserved
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package pogosh
     6  
     7  import (
     8  	"math/big"
     9  	"reflect"
    10  	"testing"
    11  )
    12  
    13  // Fake variables for the test.
    14  func getVar(name string) *big.Int {
    15  	fakeVars := map[string]*big.Int{
    16  		"x":   big.NewInt(1),
    17  		"y":   big.NewInt(123),
    18  		"z":   big.NewInt(-1),
    19  		"xyz": big.NewInt(42),
    20  	}
    21  	val, ok := fakeVars[name]
    22  	if !ok {
    23  		return big.NewInt(0)
    24  	}
    25  	return val
    26  }
    27  
    28  // The positive tests are expected to pass parsing.
    29  var arithmeticPositiveTests = []struct {
    30  	name string
    31  	in   string
    32  	out  *big.Int
    33  }{
    34  	// Constants
    35  	{"Zero",
    36  		"0",
    37  		big.NewInt(0),
    38  	},
    39  	{"Decimal",
    40  		"123",
    41  		big.NewInt(123),
    42  	},
    43  	{"Octal",
    44  		"0123",
    45  		big.NewInt(0123),
    46  	},
    47  	{"Hex",
    48  		"0x123",
    49  		big.NewInt(0x123),
    50  	},
    51  
    52  	// Order of operation
    53  	{"BEDMAS1",
    54  		"1+2*3",
    55  		big.NewInt(7),
    56  	},
    57  	{"BEDMAS2",
    58  		"(1+2)*3",
    59  		big.NewInt(9),
    60  	},
    61  	{"BEDMAS3",
    62  		"1*2+3",
    63  		big.NewInt(5),
    64  	},
    65  	{"BEDMAS4",
    66  		"-1*-2+-+-3",
    67  		big.NewInt(5),
    68  	},
    69  
    70  	// Associativity
    71  	{"Associativity1",
    72  		"1-2-3",
    73  		big.NewInt(-4),
    74  	},
    75  	{"Associativity2",
    76  		"1-2*3-4",
    77  		big.NewInt(-9),
    78  	},
    79  
    80  	// Spacing
    81  	{"Spacing",
    82  		" 1 + 3 * 4 / 3 - 8 ",
    83  		big.NewInt(-3),
    84  	},
    85  
    86  	// Conditional Operator
    87  	{"Conditional",
    88  		" 0 ? 4 : 1 ? 5 : 6 ",
    89  		big.NewInt(5),
    90  	},
    91  
    92  	// Variables
    93  	{"Variables1",
    94  		"x",
    95  		big.NewInt(1),
    96  	},
    97  	{"Variables2",
    98  		"x + y",
    99  		big.NewInt(124),
   100  	},
   101  	{"Variables3",
   102  		"xyz * 2",
   103  		big.NewInt(84),
   104  	},
   105  }
   106  
   107  func TestArithmeticPositive(t *testing.T) {
   108  	for _, tt := range arithmeticPositiveTests {
   109  		t.Run(tt.name, func(t *testing.T) {
   110  			a := Arithmetic{
   111  				getVar: getVar,
   112  				input:  tt.in,
   113  			}
   114  			got := a.evalExpression()
   115  
   116  			if !reflect.DeepEqual(got, tt.out) {
   117  				t.Errorf("got %v, want %v", got, tt.out)
   118  			}
   119  		})
   120  	}
   121  }