support postfix completion

Author: CppCXY

crates/emmylua_ls/src/handlers/completion/providers/mod.rs

@@ -8,6 +8,7 @@ mod keywords_provider;
 mod member_provider;
 mod module_path_provider;
 mod auto_require_provider;
+mod postfix_provider;
 
 use super::completion_builder::CompletionBuilder;
 
@@ -22,6 +23,7 @@ pub fn add_completions(builder: &mut CompletionBuilder) -> Option<()> {
     doc_tag_provider::add_completion(builder);
     doc_type_provider::add_completion(builder);
     doc_name_token_provider::add_completion(builder);
+    postfix_provider::add_completion(builder);
 
     Some(())
 }

crates/emmylua_ls/src/handlers/completion/providers/postfix_provider.rs

@@ -0,0 +1,187 @@
+use code_analysis::Emmyrc;
+use emmylua_parser::{LuaAstNode, LuaTokenKind};
+use lsp_types::{CompletionItem, Range};
+use rowan::{TextRange, TokenAtOffset};
+
+use crate::handlers::completion::completion_builder::CompletionBuilder;
+
+pub fn add_completion(builder: &mut CompletionBuilder) -> Option<()> {
+    if builder.is_cancelled() {
+        return None;
+    }
+
+    let emmyrc = builder.semantic_model.get_emmyrc();
+    let trigger_kind = builder.trigger_token.kind();
+    if !is_postfix_trigger(trigger_kind.into(), emmyrc) {
+        return None;
+    }
+
+    let trigger_pos = u32::from(builder.trigger_token.text_range().start());
+    let left_pos = if trigger_pos > 0 {
+        trigger_pos - 1
+    } else {
+        return None;
+    };
+
+    let left_token = match builder
+        .semantic_model
+        .get_root()
+        .syntax()
+        .token_at_offset(left_pos.into())
+    {
+        TokenAtOffset::Single(token) => token,
+        TokenAtOffset::Between(left, right) => {
+            if left.kind() == LuaTokenKind::TkName.into() {
+                left
+            } else {
+                right
+            }
+        },
+        TokenAtOffset::None => return None,
+    };
+
+    let left_token_text = left_token.text().to_string();
+    let replace_range = TextRange::new(
+        left_token.text_range().start(),
+        builder.trigger_token.text_range().end(),
+    );
+    let repalce_lsp_range = builder
+        .semantic_model
+        .get_document()
+        .to_lsp_range(replace_range)?;
+
+    add_postfix_completion(
+        builder,
+        repalce_lsp_range,
+        "if",
+        format!("if {} then\n\t$0\nend", left_token_text),
+    );
+
+    add_postfix_completion(
+        builder,
+        repalce_lsp_range,
+        "ifn",
+        format!("if not {} then\n\t$0\nend", left_token_text),
+    );
+
+    add_postfix_completion(
+        builder,
+        repalce_lsp_range,
+        "while",
+        format!("while {} do\n\t$0\nend", left_token_text),
+    );
+
+    add_postfix_completion(
+        builder,
+        repalce_lsp_range,
+        "forp",
+        format!(
+            "for ${{1:k}}, ${{2:v}} in pairs({}) do\n\t$0\nend",
+            left_token_text
+        ),
+    );
+
+    add_postfix_completion(
+        builder,
+        repalce_lsp_range,
+        "forip",
+        format!(
+            "for ${{1:i}}, ${{2:v}} in ipairs({}) do\n\t$0\nend",
+            left_token_text
+        ),
+    );
+
+    add_postfix_completion(
+        builder,
+        repalce_lsp_range,
+        "fori",
+        format!("for ${{1:i}} = 1, {} do\n\t$0\nend", left_token_text),
+    );
+
+    add_postfix_completion(
+        builder,
+        repalce_lsp_range,
+        "function",
+        format!("function {}(${{1:...}})\n\t$0\nend", left_token_text),
+    );
+
+    add_postfix_completion(
+        builder,
+        repalce_lsp_range,
+        "insert",
+        format!("table.insert({}, ${{1:value}})", left_token_text),
+    );
+
+    add_postfix_completion(
+        builder,
+        repalce_lsp_range,
+        "remove",
+        format!("table.remove({}, ${{1:index}})", left_token_text),
+    );
+
+    add_postfix_completion(
+        builder,
+        repalce_lsp_range,
+        "++",
+        format!("{0} = {0} + 1", left_token_text),
+    );
+
+    add_postfix_completion(
+        builder,
+        repalce_lsp_range,
+        "--",
+        format!("{0} = {0} - 1", left_token_text),
+    );
+
+    add_postfix_completion(
+        builder,
+        repalce_lsp_range,
+        "+n",
+        format!("{0} = {0} + $1", left_token_text),
+    );
+
+    add_postfix_completion(
+        builder,
+        repalce_lsp_range,
+        "-n",
+        format!("{0} = {0} - $1", left_token_text),
+    );
+
+    Some(())
+}
+
+fn is_postfix_trigger(trigger_kind: LuaTokenKind, emmyrc: &Emmyrc) -> bool {
+    let trigger_string = &emmyrc.completion.postfix;
+    if trigger_string.is_empty() {
+        return false;
+    }
+
+    let first_char = trigger_string.chars().next().unwrap();
+    return match first_char {
+        '.' => trigger_kind == LuaTokenKind::TkDot,
+        '@' => trigger_kind == LuaTokenKind::TkAt,
+        ':' => trigger_kind == LuaTokenKind::TkColon,
+        _ => false,
+    };
+}
+
+fn add_postfix_completion(
+    builder: &mut CompletionBuilder,
+    replace_range: Range,
+    label: &str,
+    text: String,
+) -> Option<()> {
+    let item = CompletionItem {
+        label: label.to_string(),
+        insert_text: Some(text),
+        additional_text_edits: Some(vec![lsp_types::TextEdit {
+            range: replace_range,
+            new_text: "".to_string(),
+        }]),
+        insert_text_format: Some(lsp_types::InsertTextFormat::SNIPPET),
+        ..Default::default()
+    };
+
+    builder.add_completion_item(item);
+    Some(())
+}