internal: make CompletionItem and SourceChange consistent

Before this PR, SourceChange used a bool and CompletionItem used an enum
to signify if edit is a snippet. It makes sense to use the same pattern
in both cases. `bool` feels simpler, as there's only one consumer of
this API, and all producers are encapsulated anyway (we check the
capability at the production site).

crates/ide/src/lib.rs

@@ -97,7 +97,6 @@ pub use ide_assists::{
 };
 pub use ide_completion::{
     CompletionConfig, CompletionItem, CompletionItemKind, CompletionRelevance, ImportEdit,
-    InsertTextFormat,
 };
 pub use ide_db::{
     base_db::{

crates/ide_completion/src/item.rs

@@ -39,8 +39,7 @@ pub struct CompletionItem {
     ///
     /// Typically, replaces `source_range` with new identifier.
     text_edit: TextEdit,
-
+    is_snippet: bool,
-    insert_text_format: InsertTextFormat,
 
     /// What item (struct, function, etc) are we completing.
     kind: Option<CompletionItemKind>,
@@ -272,12 +271,6 @@ pub(crate) enum CompletionKind {
     Attribute,
 }
 
-#[derive(Debug, PartialEq, Eq, Copy, Clone)]
-pub enum InsertTextFormat {
-    PlainText,
-    Snippet,
-}
-
 impl CompletionItem {
     pub(crate) fn new(
         completion_kind: CompletionKind,
@@ -290,7 +283,7 @@ impl CompletionItem {
             completion_kind,
             label,
             insert_text: None,
-            insert_text_format: InsertTextFormat::PlainText,
+            is_snippet: false,
             detail: None,
             documentation: None,
             lookup: None,
@@ -312,13 +305,13 @@ impl CompletionItem {
         self.source_range
     }
 
-    pub fn insert_text_format(&self) -> InsertTextFormat {
-        self.insert_text_format
-    }
-
     pub fn text_edit(&self) -> &TextEdit {
         &self.text_edit
     }
+    /// Whether `text_edit` is a snippet (contains `$0` markers).
+    pub fn is_snippet(&self) -> bool {
+        self.is_snippet
+    }
 
     /// Short one-line additional information, like a type
     pub fn detail(&self) -> Option<&str> {
@@ -396,7 +389,7 @@ pub(crate) struct Builder {
     import_to_add: Option<ImportEdit>,
     label: String,
     insert_text: Option<String>,
-    insert_text_format: InsertTextFormat,
+    is_snippet: bool,
     detail: Option<String>,
     documentation: Option<Documentation>,
     lookup: Option<String>,
@@ -442,8 +435,8 @@ impl Builder {
         CompletionItem {
             source_range: self.source_range,
             label,
-            insert_text_format: self.insert_text_format,
             text_edit,
+            is_snippet: self.is_snippet,
             detail: self.detail,
             documentation: self.documentation,
             lookup,
@@ -473,7 +466,7 @@ impl Builder {
         _cap: SnippetCap,
         snippet: impl Into<String>,
     ) -> &mut Builder {
-        self.insert_text_format = InsertTextFormat::Snippet;
+        self.is_snippet = true;
         self.insert_text(snippet)
     }
     pub(crate) fn kind(&mut self, kind: impl Into<CompletionItemKind>) -> &mut Builder {
@@ -485,7 +478,7 @@ impl Builder {
         self
     }
     pub(crate) fn snippet_edit(&mut self, _cap: SnippetCap, edit: TextEdit) -> &mut Builder {
-        self.insert_text_format = InsertTextFormat::Snippet;
+        self.is_snippet = true;
         self.text_edit(edit)
     }
     pub(crate) fn detail(&mut self, detail: impl Into<String>) -> &mut Builder {

crates/ide_completion/src/lib.rs

@@ -25,7 +25,7 @@ use crate::{completions::Completions, context::CompletionContext, item::Completi
 
 pub use crate::{
     config::CompletionConfig,
-    item::{CompletionItem, CompletionItemKind, CompletionRelevance, ImportEdit, InsertTextFormat},
+    item::{CompletionItem, CompletionItemKind, CompletionRelevance, ImportEdit},
 };
 
 //FIXME: split the following feature into fine-grained features.

crates/rust-analyzer/src/to_proto.rs

@@ -9,8 +9,8 @@ use ide::{
     Annotation, AnnotationKind, Assist, AssistKind, CallInfo, Cancellable, CompletionItem,
     CompletionItemKind, CompletionRelevance, Documentation, FileId, FileRange, FileSystemEdit,
     Fold, FoldKind, Highlight, HlMod, HlOperator, HlPunct, HlRange, HlTag, Indel, InlayHint,
-    InlayKind, InsertTextFormat, Markup, NavigationTarget, ReferenceAccess, RenameError, Runnable,
+    InlayKind, Markup, NavigationTarget, ReferenceAccess, RenameError, Runnable, Severity,
-    Severity, SourceChange, StructureNodeKind, SymbolKind, TextEdit, TextRange, TextSize,
+    SourceChange, StructureNodeKind, SymbolKind, TextEdit, TextRange, TextSize,
 };
 use itertools::Itertools;
 use serde_json::to_value;
@@ -92,15 +92,6 @@ pub(crate) fn documentation(documentation: Documentation) -> lsp_types::Document
     lsp_types::Documentation::MarkupContent(markup_content)
 }
 
-pub(crate) fn insert_text_format(
-    insert_text_format: InsertTextFormat,
-) -> lsp_types::InsertTextFormat {
-    match insert_text_format {
-        InsertTextFormat::Snippet => lsp_types::InsertTextFormat::Snippet,
-        InsertTextFormat::PlainText => lsp_types::InsertTextFormat::PlainText,
-    }
-}
-
 pub(crate) fn completion_item_kind(
     completion_item_kind: CompletionItemKind,
 ) -> lsp_types::CompletionItemKind {
@@ -278,7 +269,9 @@ fn completion_item(
         lsp_item.command = Some(command::trigger_parameter_hints());
     }
 
-    lsp_item.insert_text_format = Some(insert_text_format(item.insert_text_format()));
+    if item.is_snippet() {
+        lsp_item.insert_text_format = Some(lsp_types::InsertTextFormat::Snippet);
+    }
     if enable_imports_on_the_fly {
         if let Some(import_edit) = item.import_to_add() {
             let import_path = &import_edit.import.import_path;