customize completion candidates for some args

cli/commands/args.rs

@@ -1,6 +1,7 @@
 use clap::{Args, ValueEnum};
+use clap_complete::{ArgValueCompleter, CompletionCandidate, PathCompleter};
 
-use crate::input::OutputMode;
+use crate::{input::OutputMode, opcodes_dictionary::OPCODE_DESCRIPTIONS};
 
 #[derive(Debug, Clone, Args)]
 pub struct ExitArgs {
@@ -12,13 +13,17 @@ pub struct ExitArgs {
 #[derive(Debug, Clone, Args)]
 pub struct OpenArgs {
     /// Path to open database
+    #[arg(add = ArgValueCompleter::new(PathCompleter::file()))]
     pub path: String,
+    // TODO see how to have this completed with the output of List Vfs function
+    // Currently not possible to pass arbitrary
     /// Name of VFS
     pub vfs_name: Option<String>,
 }
 
 #[derive(Debug, Clone, Args)]
 pub struct SchemaArgs {
+    // TODO depends on PRAGMA table_list for completions
     /// Table name to visualize schema
     pub table_name: Option<String>,
 }
@@ -26,6 +31,7 @@ pub struct SchemaArgs {
 #[derive(Debug, Clone, Args)]
 pub struct SetOutputArgs {
     /// File path to send output to
+    #[arg(add = ArgValueCompleter::new(PathCompleter::file()))]
     pub path: Option<String>,
 }
 
@@ -35,15 +41,40 @@ pub struct OutputModeArgs {
     pub mode: OutputMode,
 }
 
+fn opcodes_completer(current: &std::ffi::OsStr) -> Vec<CompletionCandidate> {
+    let mut completions = vec![];
+
+    let Some(current) = current.to_str() else {
+        return completions;
+    };
+
+    let current = current.to_lowercase();
+
+    let opcodes = &OPCODE_DESCRIPTIONS;
+
+    for op in opcodes {
+        // TODO if someone know how to do prefix_match with case insensitve in Rust
+        // without converting the String to lowercase first, please fix this.
+        let op_name = op.name.to_ascii_lowercase();
+        if op_name.starts_with(&current) {
+            completions.push(CompletionCandidate::new(op.name).help(Some(op.description.into())));
+        }
+    }
+
+    completions
+}
+
 #[derive(Debug, Clone, Args)]
 pub struct OpcodesArgs {
     /// Opcode to display description
+    #[arg(add = ArgValueCompleter::new(opcodes_completer))]
     pub opcode: Option<String>,
 }
 
 #[derive(Debug, Clone, Args)]
 pub struct CwdArgs {
     /// Target directory
+    #[arg(add = ArgValueCompleter::new(PathCompleter::dir()))]
     pub directory: String,
 }
 
@@ -72,11 +103,6 @@ pub struct TablesArgs {
 #[derive(Debug, Clone, Args)]
 pub struct LoadExtensionArgs {
     /// Path to extension file
-    pub path: String,
-}
-
-#[derive(Debug, Clone, Args)]
-pub struct ListVfsArgs {
-    /// Path to extension file
+    #[arg(add = ArgValueCompleter::new(PathCompleter::file()))]
     pub path: String,
 }

cli/commands/mod.rs

@@ -35,9 +35,6 @@ pub enum Command {
     /// Open a database file
     #[command(display_name = ".open")]
     Open(OpenArgs),
-    /// Print this message or the help of the given subcommand(s)
-    // #[command(display_name = ".help")]
-    // Help,
     /// Display schema for a table
     #[command(display_name = ".schema")]
     Schema(SchemaArgs),