Provide completion for BibTeX commands

src/completion/bibtex/kernel_command.rs

@@ -0,0 +1,104 @@
+use crate::completion::factory;
+use crate::completion::factory::LatexComponentId;
+use crate::completion::latex::kernel_primitives::KERNEL_COMMANDS;
+use crate::feature::FeatureRequest;
+use crate::syntax::bibtex::{BibtexFinder, BibtexNode, BibtexVisitor};
+use crate::syntax::text::SyntaxNode;
+use crate::syntax::SyntaxTree;
+use lsp_types::{CompletionItem, CompletionParams};
+use std::borrow::Cow;
+
+pub struct BibtexKernelCommandCompletionProvider;
+
+impl BibtexKernelCommandCompletionProvider {
+    pub async fn execute(request: &FeatureRequest<CompletionParams>) -> Vec<CompletionItem> {
+        if let SyntaxTree::Bibtex(tree) = &request.document.tree {
+            let mut finder = BibtexFinder::new(request.params.position);
+            finder.visit_root(&tree.root);
+            if let Some(BibtexNode::Command(command)) = finder.results.last() {
+                if command.token.range().contains(request.params.position)
+                    && command.token.start().character != request.params.position.character
+                {
+                    return Self::generate_items();
+                }
+            }
+        }
+        Vec::new()
+    }
+
+    fn generate_items() -> Vec<CompletionItem> {
+        KERNEL_COMMANDS
+            .iter()
+            .map(|command| factory::create_command(Cow::from(*command), &LatexComponentId::Kernel))
+            .collect()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::completion::latex::data::types::LatexComponentDatabase;
+    use crate::feature::FeatureSpec;
+    use crate::test_feature;
+    use lsp_types::Position;
+
+    #[test]
+    fn test_inside_command() {
+        let items = test_feature!(
+            BibtexKernelCommandCompletionProvider,
+            FeatureSpec {
+                files: vec![FeatureSpec::file("foo.bib", "@article{foo, bar=\n\\}")],
+                main_file: "foo.bib",
+                position: Position::new(1, 1),
+                new_name: "",
+                component_database: LatexComponentDatabase::default(),
+            }
+        );
+        assert_eq!(items.len() > 0, true);
+    }
+
+    #[test]
+    fn test_start_of_command() {
+        let items = test_feature!(
+            BibtexKernelCommandCompletionProvider,
+            FeatureSpec {
+                files: vec![FeatureSpec::file("foo.bib", "@article{foo, bar=\n\\}")],
+                main_file: "foo.bib",
+                position: Position::new(1, 0),
+                new_name: "",
+                component_database: LatexComponentDatabase::default(),
+            }
+        );
+        assert_eq!(items.len() == 0, true);
+    }
+
+    #[test]
+    fn test_inside_text() {
+        let items = test_feature!(
+            BibtexKernelCommandCompletionProvider,
+            FeatureSpec {
+                files: vec![FeatureSpec::file("foo.bib", "@article{foo, bar=\n}")],
+                main_file: "foo.bib",
+                position: Position::new(1, 0),
+                new_name: "",
+                component_database: LatexComponentDatabase::default(),
+            }
+        );
+        assert_eq!(items.len() == 0, true);
+    }
+
+    #[test]
+    fn test_latex() {
+        let items = test_feature!(
+            BibtexKernelCommandCompletionProvider,
+            FeatureSpec {
+                files: vec![FeatureSpec::file("foo.tex", "\\")],
+                main_file: "foo.tex",
+                position: Position::new(0, 1),
+                new_name: "",
+                component_database: LatexComponentDatabase::default(),
+            }
+        );
+        assert_eq!(items.len() == 0, true);
+    }
+}

src/completion/bibtex/mod.rs

@@ -1,2 +1,3 @@
 pub mod entry_type;
 pub mod field_name;
+pub mod kernel_command;

src/completion/mod.rs

@@ -5,6 +5,7 @@ mod quality;
 
 use self::bibtex::entry_type::BibtexEntryTypeCompletionProvider;
 use self::bibtex::field_name::BibtexFieldNameCompletionProvider;
+use self::bibtex::kernel_command::BibtexKernelCommandCompletionProvider;
 use self::latex::begin_command::LatexBeginCommandCompletionProvider;
 use self::latex::citation::LatexCitationCompletionProvider;
 use self::latex::color::LatexColorCompletionProvider;
@@ -36,6 +37,7 @@ impl CompletionProvider {
                     &request,
                     BibtexEntryTypeCompletionProvider,
                     BibtexFieldNameCompletionProvider,
+                    BibtexKernelCommandCompletionProvider,
                     LatexKernelEnvironmentCompletionProvider,
                     LatexPgfLibraryCompletionProvider,
                     LatexTikzLibraryCompletionProvider,