fallow_output/
json_paths.rs

1//! Shared JSON path post-processing for output contracts.
2
3/// Recursively strip a project-root prefix from all string values in a JSON
4/// tree.
5///
6/// This keeps machine output relative to the analyzed root even when upstream
7/// analysis stages temporarily carry absolute paths.
8pub fn strip_root_prefix(value: &mut serde_json::Value, prefix: &str) {
9    match value {
10        serde_json::Value::String(s) => strip_root_prefix_from_string(s, prefix),
11        serde_json::Value::Array(items) => {
12            for item in items {
13                strip_root_prefix(item, prefix);
14            }
15        }
16        serde_json::Value::Object(map) => {
17            for (key, value) in map.iter_mut() {
18                if key == VERBATIM_KEY {
19                    continue;
20                }
21                strip_root_prefix(value, prefix);
22            }
23        }
24        _ => {}
25    }
26}
27
28/// The one envelope member whose strings are not paths of the analyzed tree.
29///
30/// `request_outcomes` echoes what the user asked for (`requested`) and the
31/// sentence the CLI printed (`message`), and its contract promises both
32/// unchanged. Rewriting them would turn a `--sarif-file` under the root into a
33/// path the consumer cannot open from its own working directory, and would
34/// make the wire sentence differ from the stderr line it mirrors.
35const VERBATIM_KEY: &str = "request_outcomes";
36
37fn strip_root_prefix_from_string(value: &mut String, prefix: &str) {
38    if let Some(rest) = value.strip_prefix(prefix) {
39        *value = rest.to_string();
40        return;
41    }
42
43    let normalized = normalize_uri(value);
44    let normalized_prefix = normalize_uri(prefix);
45    if let Some(rest) = normalized.strip_prefix(&normalized_prefix) {
46        *value = rest.to_string();
47    } else if let Some(stripped) = strip_embedded_root_prefixes(&normalized, &normalized_prefix) {
48        *value = stripped;
49    }
50}
51
52/// Normalize a path string to a valid URI: forward slashes and percent-encoded
53/// brackets.
54///
55/// Brackets (`[`, `]`) are not valid in URI path segments per RFC 3986 and
56/// cause SARIF / CodeClimate validation warnings for framework routes such as
57/// Next.js dynamic segments.
58#[must_use]
59pub fn normalize_uri(path: &str) -> String {
60    path.replace('\\', "/")
61        .replace('[', "%5B")
62        .replace(']', "%5D")
63}
64
65fn strip_embedded_root_prefixes(value: &str, prefix: &str) -> Option<String> {
66    let mut output = String::with_capacity(value.len());
67    let mut changed = false;
68    let mut last = 0;
69    let mut search_from = 0;
70
71    while let Some(offset) = value[search_from..].find(prefix) {
72        let index = search_from + offset;
73        let can_strip = index > 0
74            && value[..index]
75                .chars()
76                .next_back()
77                .is_some_and(is_embedded_path_boundary);
78
79        if can_strip {
80            output.push_str(&value[last..index]);
81            last = index + prefix.len();
82            changed = true;
83        }
84
85        search_from = index + prefix.len();
86    }
87
88    if changed {
89        output.push_str(&value[last..]);
90        Some(output)
91    } else {
92        None
93    }
94}
95
96fn is_embedded_path_boundary(c: char) -> bool {
97    c.is_whitespace() || matches!(c, '"' | '\'' | '`' | '(' | '[' | '{' | ':' | '=')
98}
99
100#[cfg(test)]
101mod tests {
102    use serde_json::json;
103
104    use super::*;
105
106    #[test]
107    fn strips_root_from_nested_strings() {
108        let mut value = json!({
109            "path": "/project/src/index.ts",
110            "items": ["/project/src/a.ts", { "path": "/project/src/b.ts" }]
111        });
112
113        strip_root_prefix(&mut value, "/project/");
114
115        assert_eq!(value["path"], "src/index.ts");
116        assert_eq!(value["items"][0], "src/a.ts");
117        assert_eq!(value["items"][1]["path"], "src/b.ts");
118    }
119
120    #[test]
121    fn normalizes_windows_separators_before_stripping() {
122        let mut value = json!("C:\\repo\\src\\index.ts");
123
124        strip_root_prefix(&mut value, "C:/repo/");
125
126        assert_eq!(value, json!("src/index.ts"));
127    }
128
129    #[test]
130    fn rewrites_embedded_path_strings() {
131        let mut value = json!("See /project/src/a.ts and /project/src/b.ts");
132
133        strip_root_prefix(&mut value, "/project/");
134
135        assert_eq!(value, json!("See src/a.ts and src/b.ts"));
136    }
137
138    #[test]
139    fn leaves_request_outcomes_verbatim_while_stripping_its_siblings() {
140        let mut value = json!({
141            "path": "/project/src/index.ts",
142            "request_outcomes": {
143                "sarif-file": {
144                    "requested": "/project/out/results.sarif",
145                    "message": "failed to write SARIF file '/project/out/results.sarif'"
146                }
147            }
148        });
149
150        strip_root_prefix(&mut value, "/project/");
151
152        assert_eq!(value["path"], "src/index.ts");
153        let entry = &value["request_outcomes"]["sarif-file"];
154        assert_eq!(entry["requested"], "/project/out/results.sarif");
155        assert_eq!(
156            entry["message"],
157            "failed to write SARIF file '/project/out/results.sarif'"
158        );
159    }
160
161    #[test]
162    fn leaves_non_matching_strings_unchanged() {
163        let mut value = json!("src/index.ts");
164
165        strip_root_prefix(&mut value, "/project/");
166
167        assert_eq!(value, json!("src/index.ts"));
168    }
169
170    #[test]
171    fn normalize_uri_rewrites_backslashes_and_brackets() {
172        assert_eq!(
173            normalize_uri("app\\[lang]\\posts\\[id].tsx"),
174            "app/%5Blang%5D/posts/%5Bid%5D.tsx"
175        );
176    }
177}
fallow_output/json_paths.rs

fallow_output/
json_paths.rs
