chore: extract out src/nu.rs; add tests

src/main.rs

@@ -1,14 +1,15 @@
 #![deny(clippy::all, unsafe_code)]
 
 use std::borrow::Cow;
-use std::path::PathBuf;
 
-use serde::Deserialize;
+use nu::{convert_position, IdeComplete, IdeGotoDef, IdeHover};
 use serde_json::Value;
 use tower_lsp::jsonrpc::Result;
 use tower_lsp::lsp_types::*;
 use tower_lsp::{Client, LanguageServer, LspService, Server};
 
+mod nu;
+
 #[derive(Debug)]
 struct Backend {
     client: Client,
@@ -211,49 +212,6 @@ impl LanguageServer for Backend {
     }
 }
 
-#[derive(Deserialize)]
-struct IdeComplete {
-    completions: Vec<String>,
-}
-
-#[derive(Deserialize)]
-struct IdeGotoDef {
-    // end: usize,
-    file: PathBuf,
-    // start: usize,
-}
-
-#[derive(Deserialize)]
-struct IdeHover {
-    hover: String,
-    // span: Option<Range>,
-}
-
-// ported from https://github.com/nushell/vscode-nushell-lang
-fn convert_position(position: &Position, text: &str) -> usize {
-    let mut line = 0;
-    let mut character = 0;
-    let buffer = text.as_bytes();
-
-    let mut i = 0;
-    while i < buffer.len() {
-        if line == position.line && character == position.character {
-            return i;
-        }
-
-        if buffer[i] == 0x0a {
-            line += 1;
-            character = 0;
-        } else {
-            character += 1;
-        }
-
-        i += 1;
-    }
-
-    i
-}
-
 #[tokio::main]
 async fn main() {
     let stdin = tokio::io::stdin();

src/nu.rs

@@ -0,0 +1,103 @@
+use std::path::PathBuf;
+
+use serde::Deserialize;
+use tower_lsp::lsp_types::Position;
+
+#[derive(Deserialize)]
+pub(crate) struct IdeComplete {
+    pub completions: Vec<String>,
+}
+
+#[derive(Deserialize)]
+pub(crate) struct IdeGotoDef {
+    // end: usize,
+    pub file: PathBuf,
+    // start: usize,
+}
+
+#[derive(Deserialize)]
+pub(crate) struct IdeHover {
+    pub hover: String,
+    // span: Option<Range>,
+}
+
+// ported from https://github.com/nushell/vscode-nushell-lang
+pub(crate) fn convert_position(position: &Position, text: &str) -> usize {
+    let mut line = 0;
+    let mut character = 0;
+    let buffer = text.as_bytes();
+
+    let mut i = 0;
+    while i < buffer.len() {
+        if line == position.line && character == position.character {
+            return i;
+        }
+
+        if buffer[i] == 0x0a {
+            line += 1;
+            character = 0;
+        } else {
+            character += 1;
+        }
+
+        i += 1;
+    }
+
+    i
+}
+
+// ported from https://github.com/nushell/vscode-nushell-lang
+#[allow(dead_code)]
+pub(crate) fn convert_span() -> Position {
+    todo!()
+}
+
+// ported from https://github.com/nushell/vscode-nushell-lang
+#[allow(dead_code)]
+pub(crate) fn find_line_breaks(text: &str) -> Vec<usize> {
+    text.as_bytes()
+        .iter()
+        .enumerate()
+        .filter_map(|(i, b)| if b == &0x0a { Some(i) } else { None })
+        .collect()
+}
+
+// ported from https://github.com/nushell/vscode-nushell-lang
+#[allow(dead_code)]
+pub(crate) fn lower_bound_binary_search(_offset: usize, _line_breaks: &[usize]) -> Position {
+    Position::default()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    static FIXTURE: &str = "
+#! /usr/bin/env nu
+def main [] {
+    ls | sort-by 'size' | first
+}
+";
+
+    #[test]
+    fn convert_position_ok() {
+        assert_eq!(convert_position(&Position::default(), FIXTURE.trim()), 0);
+
+        // `ls | ...`
+        assert_eq!(
+            convert_position(
+                &Position {
+                    line: 2,
+                    character: 4
+                },
+                FIXTURE.trim()
+            ),
+            37
+        );
+    }
+
+    #[test]
+    fn find_line_breaks_ok() {
+        assert_eq!(find_line_breaks(FIXTURE.trim()), vec![18, 32, 64]);
+    }
+}