debtmap 0.16.4

Code complexity and technical debt analyzer
Documentation 
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
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178

use crate::core::{FileMetrics, FunctionMetrics};
use crate::refactoring::{
    DetectedPattern, EffortEstimate, FunctionRole, FunctionalPattern, ImperativePattern,
    PatternType, Priority, RefactoringDetector, RefactoringOpportunity, TransformationStep,
};

pub struct FunctionalTransformationDetector;

impl RefactoringDetector for FunctionalTransformationDetector {
    fn detect_opportunities(
        &self,
        function: &FunctionMetrics,
        _file: &FileMetrics,
        _role: &FunctionRole,
        patterns: &[DetectedPattern],
    ) -> Vec<RefactoringOpportunity> {
        let mut opportunities = Vec::new();

        // Check for imperative patterns that can be converted
        let imperative_patterns: Vec<ImperativePattern> = patterns
            .iter()
            .filter_map(|p| match &p.pattern_type {
                PatternType::ImperativeLoop => Some(ImperativePattern::MutableLoop),
                PatternType::MutableState => Some(ImperativePattern::StateModification),
                _ => None,
            })
            .collect();

        if !imperative_patterns.is_empty() {
            opportunities.push(RefactoringOpportunity::ConvertToFunctionalStyle {
                imperative_function: function.name.clone(),
                current_patterns: imperative_patterns.clone(),
                target_patterns: suggest_functional_alternatives(&imperative_patterns),
                transformation_steps: generate_transformation_steps(&imperative_patterns),
                benefits: vec![
                    "Eliminate mutable state".to_string(),
                    "Make code more declarative".to_string(),
                    "Improve testability".to_string(),
                    "Enable safe parallelization".to_string(),
                ],
                effort_estimate: EffortEstimate::Low,
            });
        }

        opportunities
    }

    fn priority(&self) -> Priority {
        Priority::Medium
    }
}

fn suggest_functional_alternatives(imperative: &[ImperativePattern]) -> Vec<FunctionalPattern> {
    let mut patterns = Vec::new();

    for pattern in imperative {
        match pattern {
            ImperativePattern::MutableLoop => {
                patterns.push(FunctionalPattern::MapOverLoop);
                patterns.push(FunctionalPattern::FilterPredicate);
                patterns.push(FunctionalPattern::FoldAccumulation);
            }
            ImperativePattern::StateModification => {
                patterns.push(FunctionalPattern::FoldAccumulation);
                patterns.push(FunctionalPattern::Monadic(
                    crate::refactoring::MonadicPattern::State,
                ));
            }
            ImperativePattern::NestedConditions => {
                patterns.push(FunctionalPattern::PatternMatchOverIfElse);
                patterns.push(FunctionalPattern::Monadic(
                    crate::refactoring::MonadicPattern::Option,
                ));
            }
            ImperativePattern::SideEffectMixing => {
                patterns.push(FunctionalPattern::ComposeFunctions);
                patterns.push(FunctionalPattern::Pipeline);
            }
        }
    }

    patterns
}

fn generate_transformation_steps(imperative: &[ImperativePattern]) -> Vec<TransformationStep> {
    let mut steps = Vec::new();

    for pattern in imperative {
        match pattern {
            ImperativePattern::MutableLoop => {
                steps.push(TransformationStep {
                    description: "Replace for loop with iterator methods".to_string(),
                    pattern_applied: FunctionalPattern::MapOverLoop,
                });
                steps.push(TransformationStep {
                    description: "Extract loop body as pure function".to_string(),
                    pattern_applied: FunctionalPattern::ComposeFunctions,
                });
            }
            ImperativePattern::StateModification => {
                steps.push(TransformationStep {
                    description: "Replace mutable variables with fold/reduce".to_string(),
                    pattern_applied: FunctionalPattern::FoldAccumulation,
                });
            }
            ImperativePattern::NestedConditions => {
                steps.push(TransformationStep {
                    description: "Convert if-else chains to pattern matching".to_string(),
                    pattern_applied: FunctionalPattern::PatternMatchOverIfElse,
                });
            }
            ImperativePattern::SideEffectMixing => {
                steps.push(TransformationStep {
                    description: "Extract side effects to boundaries".to_string(),
                    pattern_applied: FunctionalPattern::Pipeline,
                });
            }
        }
    }

    steps
}

pub struct LoopToFunctionalDetector;

impl RefactoringDetector for LoopToFunctionalDetector {
    fn detect_opportunities(
        &self,
        function: &FunctionMetrics,
        _file: &FileMetrics,
        _role: &FunctionRole,
        patterns: &[DetectedPattern],
    ) -> Vec<RefactoringOpportunity> {
        let has_loops = patterns
            .iter()
            .any(|p| matches!(p.pattern_type, PatternType::ImperativeLoop));

        if has_loops && function.cyclomatic > 3 {
            vec![RefactoringOpportunity::ConvertToFunctionalStyle {
                imperative_function: function.name.clone(),
                current_patterns: vec![ImperativePattern::MutableLoop],
                target_patterns: vec![
                    FunctionalPattern::MapOverLoop,
                    FunctionalPattern::FilterPredicate,
                    FunctionalPattern::FoldAccumulation,
                ],
                transformation_steps: vec![
                    TransformationStep {
                        description: "Identify loop purpose (transform/filter/aggregate)"
                            .to_string(),
                        pattern_applied: FunctionalPattern::MapOverLoop,
                    },
                    TransformationStep {
                        description: "Replace loop with appropriate iterator method".to_string(),
                        pattern_applied: FunctionalPattern::FilterPredicate,
                    },
                    TransformationStep {
                        description: "Extract loop body as pure function".to_string(),
                        pattern_applied: FunctionalPattern::ComposeFunctions,
                    },
                ],
                benefits: vec![
                    "More declarative and readable".to_string(),
                    "Eliminates off-by-one errors".to_string(),
                    "Enables lazy evaluation".to_string(),
                    "Parallelizable with rayon".to_string(),
                ],
                effort_estimate: EffortEstimate::Low,
            }]
        } else {
            vec![]
        }
    }

    fn priority(&self) -> Priority {
        Priority::Medium
    }
}