Custom JSON formatter that works with template syntax (#128)

src-tauri/yaak_templates/src/format.rs

@@ -0,0 +1,230 @@
+enum FormatState {
+    TemplateTag,
+    String,
+    None,
+}
+
+/// Formats JSON that might contain template tags (skipped entirely)
+pub fn format_json(text: &str, tab: &str) -> String {
+    let mut chars = text.chars().peekable();
+
+    let mut new_json = "".to_string();
+    let mut depth = 0;
+    let mut state = FormatState::None;
+
+    loop {
+        let rest_of_chars = chars.clone();
+        let current_char = match chars.next() {
+            None => break,
+            Some(c) => c,
+        };
+
+        // Handle JSON string states
+        if let FormatState::String = state {
+            match current_char {
+                '"' => {
+                    state = FormatState::None;
+                    new_json.push(current_char);
+                    continue;
+                }
+                '\\' => {
+                    new_json.push(current_char);
+                    if let Some(c) = chars.next() {
+                        new_json.push(c);
+                    }
+                    continue;
+                }
+                _ => {
+                    new_json.push(current_char);
+                    continue;
+                }
+            }
+        }
+        // Close Template tag states
+        if let FormatState::TemplateTag = state {
+            if rest_of_chars.take(2).collect::<String>() == "]}" {
+                state = FormatState::None;
+                new_json.push_str("]}");
+                chars.next(); // Skip the second closing bracket
+                continue;
+            } else {
+                new_json.push(current_char);
+                continue;
+            }
+        }
+
+        if rest_of_chars.take(3).collect::<String>() == "${[" {
+            state = FormatState::TemplateTag;
+            new_json.push_str("${[");
+            chars.next(); // Skip {
+            chars.next(); // Skip [
+            continue;
+        }
+
+        match current_char {
+            ',' => {
+                new_json.push(current_char);
+                new_json.push('\n');
+                new_json.push_str(tab.to_string().repeat(depth).as_str());
+            }
+            '{' => match chars.peek() {
+                Some('}') => {
+                    new_json.push(current_char);
+                    new_json.push('}');
+                }
+                _ => {
+                    depth += 1;
+                    new_json.push(current_char);
+                    new_json.push('\n');
+                    new_json.push_str(tab.to_string().repeat(depth).as_str());
+                }
+            },
+            '[' => match chars.peek() {
+                Some(']') => {
+                    new_json.push(current_char);
+                    new_json.push(']');
+                }
+                _ => {
+                    depth += 1;
+                    new_json.push(current_char);
+                    new_json.push('\n');
+                    new_json.push_str(tab.to_string().repeat(depth).as_str());
+                }
+            },
+            '}' => {
+                depth -= 1;
+                new_json.push('\n');
+                new_json.push_str(tab.to_string().repeat(depth).as_str());
+                new_json.push(current_char);
+                // Pad with space if the next char is not a comma
+                if let Some(',') = chars.peek() {
+                    new_json.push(' ');
+                }
+            }
+            ']' => {
+                depth -= 1;
+                new_json.push('\n');
+                new_json.push_str(tab.to_string().repeat(depth).as_str());
+                new_json.push(current_char);
+                // Pad with space if the next char is not a comma
+                if let Some(',') = chars.peek() {
+                    new_json.push(' ');
+                }
+            }
+            ':' => {
+                new_json.push(current_char);
+                new_json.push(' '); // Pad with space
+            }
+            '"' => {
+                state = FormatState::String;
+                new_json.push(current_char);
+            }
+            _ => {
+                if current_char == ' '
+                    || current_char == '\n'
+                    || current_char == '\t'
+                    || current_char == '\r'
+                {
+                    // Don't add these
+                } else {
+                    new_json.push(current_char);
+                }
+            }
+        }
+    }
+
+    // Replace only lines containing whitespace with nothing
+    new_json
+        .lines()
+        .filter(|line| !line.trim().is_empty()) // Filter out whitespace-only lines
+        .collect::<Vec<&str>>() // Collect the non-empty lines into a vector
+        .join("\n") // Join the lines back into a single string
+}
+
+#[cfg(test)]
+mod test {
+    use crate::format::format_json;
+
+    #[test]
+    fn test_simple_object() {
+        assert_eq!(
+            format_json(r#"{"foo":"bar","baz":"qux"}"#, "  "),
+            r#"
+{
+  "foo": "bar",
+  "baz": "qux"
+}
+"#
+            .trim()
+        );
+    }
+
+    #[test]
+    fn test_simple_array() {
+        assert_eq!(
+            format_json(r#"["foo","bar","baz","qux"]"#, "  "),
+            r#"
+[
+  "foo",
+  "bar",
+  "baz",
+  "qux"
+]
+"#
+            .trim()
+        );
+    }
+
+    #[test]
+    fn test_extra_whitespace() {
+        assert_eq!(
+            format_json(
+                r#"["foo",   "bar",  "baz","qux"
+
+            ]"#,
+                "  "
+            ),
+            r#"
+[
+  "foo",
+  "bar",
+  "baz",
+  "qux"
+]
+"#
+            .trim()
+        );
+    }
+
+    #[test]
+    fn test_invalid_json() {
+        assert_eq!(
+            format_json(r#"["foo", {"bar",  }"baz",["qux" ]]"#, "  "),
+            r#"
+[
+  "foo",
+  {
+    "bar",
+  }"baz",
+  [
+    "qux"
+  ]
+]
+"#
+            .trim()
+        );
+    }
+
+    #[test]
+    fn test_skip_template_tags() {
+        assert_eq!(
+            format_json(r#"{"foo":${[ fn("hello", "world") ]} }"#, "  "),
+            r#"
+{
+  "foo": ${[ fn("hello", "world") ]}
+}
+"#
+            .trim()
+        );
+    }
+}

src-tauri/yaak_templates/src/lib.rs

@@ -1,5 +1,6 @@
 pub mod parser;
 pub mod renderer;
+pub mod format;
 
 pub use parser::*;
 pub use renderer::*;