File size: 5,046 Bytes
d5bfab8
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
use std::collections::HashMap;
use std::fs;
use std::path::{Path, PathBuf};
use anyhow::Context;
use lazy_static::lazy_static;
use regex::Regex;

lazy_static! {
    // Extract the terms row from a loda .asm program
    // The `(?m)` enables multiline matching.
    static ref EXTRACT_TERMS_FROM_LODA_PROGRAM: Regex = Regex::new(
        "(?m)^; (-?\\d+(?:,-?\\d+)+)$"
    ).unwrap();
}

/// Extract the first `terms comment` from a program
/// 
/// Returns None if there is no `terms comment`.
pub fn terms_from_program(program_path: &Path) -> anyhow::Result<Option<String>> {
    let program_contents: String = fs::read_to_string(program_path)
        .with_context(|| format!("Read program from {:?}", program_path))?;
    let re = &EXTRACT_TERMS_FROM_LODA_PROGRAM;
    let captures = match re.captures(&program_contents) {
        Some(value) => value,
        None => {
            return Ok(None);
        }
    };
    let capture1: &str = captures.get(1).map_or("", |m| m.as_str());
    let terms_string: String = capture1.to_string();
    Ok(Some(terms_string))
}

#[allow(dead_code)]
pub type PathTermsMap = HashMap::<PathBuf,String>;

/// Populate a `HashMap` with terms extracted from programs.
#[allow(dead_code)]
pub fn terms_from_programs(paths: &Vec<PathBuf>) -> anyhow::Result<PathTermsMap> {
    let mut path_terms_map = PathTermsMap::with_capacity(paths.len());
    for path in paths {
        if let Some(terms) = terms_from_program(&path)? {
            path_terms_map.insert(PathBuf::from(path), terms);
        }
    }
    Ok(path_terms_map)
}

#[cfg(test)]
mod tests {
    use super::*;
    use std::path::PathBuf;
    use std::fs;
    use std::error::Error;
    use std::fs::File;
    use std::io::prelude::*;

    #[test]
    fn test_10000_terms_from_program_ok() -> Result<(), Box<dyn Error>> {
        // Arrange
        let tempdir = tempfile::tempdir().unwrap();
        let basedir = PathBuf::from(&tempdir.path()).join("test_10000_terms_from_program_ok");
        fs::create_dir(&basedir)?;
        let input_path: PathBuf = basedir.join("input.asm");
        let input_content = 
r#"; A000321: H_n(-1/2), where H_n(x) is Hermite polynomial of degree n.
; Submitted by GolfSierra
; 1,-1,-1,5,1,-41,31,461,-895,-6481,22591,107029,-604031,-1964665,17669471

mov $2,1
lpb $0
  sub $0,1
  add $1,$2
  mul $1,2
  sub $2,$1
  add $1,$2
  mul $1,$0
lpe
mov $0,$2
"#;

        let mut input_file = File::create(&input_path)?;
        input_file.write_all(input_content.as_bytes())?;

        // Act
        let optional_terms: Option<String> = terms_from_program(&input_path)?;
        
        // Assert
        let actual: String = optional_terms.expect("Expected a string with the terms");
        assert_eq!(actual, "1,-1,-1,5,1,-41,31,461,-895,-6481,22591,107029,-604031,-1964665,17669471");
        Ok(())
    }

    #[test]
    fn test_10001_terms_from_program_ok() -> Result<(), Box<dyn Error>> {
        // Arrange
        let tempdir = tempfile::tempdir().unwrap();
        let basedir = PathBuf::from(&tempdir.path()).join("test_10001_terms_from_program_ok");
        fs::create_dir(&basedir)?;
        let input_path: PathBuf = basedir.join("input.asm");
        let input_content = 
r#"; I'm an tiny program
; without a "terms comment"
mul $0,2
; placeholder footer
"#;

        let mut input_file = File::create(&input_path)?;
        input_file.write_all(input_content.as_bytes())?;

        // Act
        let optional_terms: Option<String> = terms_from_program(&input_path)?;
        
        // Assert
        assert!(optional_terms.is_none());
        Ok(())
    }

    #[test]
    fn test_10002_terms_from_program_ok() -> Result<(), Box<dyn Error>> {
        // Arrange
        let tempdir = tempfile::tempdir().unwrap();
        let basedir = PathBuf::from(&tempdir.path()).join("test_10002_terms_from_program_ok");
        fs::create_dir(&basedir)?;
        let input_path: PathBuf = basedir.join("input.asm");
        let input_content = 
r#"; Program with multiple terms comments
; 1,1,1,1,1,1,1
; 2,2,2,2,2,2,2
; 3,3,3,3,3,3,3
; Always picks the first terms comment
"#;

        let mut input_file = File::create(&input_path)?;
        input_file.write_all(input_content.as_bytes())?;

        // Act
        let optional_terms: Option<String> = terms_from_program(&input_path)?;
        
        // Assert
        let actual: String = optional_terms.expect("Expected a string with the terms");
        assert_eq!(actual, "1,1,1,1,1,1,1");
        Ok(())
    }

    #[test]
    fn test_20000_terms_from_program_error_no_such_file() -> Result<(), Box<dyn Error>> {
        // Arrange
        let tempdir = tempfile::tempdir().unwrap();
        let basedir = PathBuf::from(&tempdir.path()).join("test_20000_terms_from_program_error_no_such_file");
        fs::create_dir(&basedir)?;
        let input_path: PathBuf = basedir.join("non-existing");

        // Act
        let result = terms_from_program(&input_path);
        
        // Assert
        assert!(result.is_err());
        Ok(())
    }
}