add initial conv module

Author: JasperDeSutter

wasm-demo/src/conv.rs

@@ -0,0 +1,72 @@
+use super::return_types;
+use ra_ide_api::{CompletionItemKind, FileId, FilePosition, LineCol, LineIndex};
+use ra_syntax::TextRange;
+
+pub trait Conv {
+    type Output;
+    fn conv(self) -> Self::Output;
+}
+
+pub trait ConvWith<CTX> {
+    type Output;
+    fn conv_with(self, ctx: CTX) -> Self::Output;
+}
+
+#[derive(Clone, Copy)]
+pub struct Position {
+    pub line_number: u32,
+    pub column: u32,
+}
+
+impl ConvWith<(&LineIndex, FileId)> for Position {
+    type Output = FilePosition;
+
+    fn conv_with(self, (line_index, file_id): (&LineIndex, FileId)) -> Self::Output {
+        let line_col = LineCol { line: self.line_number - 1, col_utf16: self.column - 1 };
+        let offset = line_index.offset(line_col);
+        FilePosition { file_id, offset }
+    }
+}
+
+impl ConvWith<&LineIndex> for TextRange {
+    type Output = return_types::Range;
+
+    fn conv_with(self, line_index: &LineIndex) -> Self::Output {
+        let start = line_index.line_col(self.start());
+        let end = line_index.line_col(self.end());
+
+        return_types::Range {
+            startLineNumber: start.line + 1,
+            startColumn: start.col_utf16 + 1,
+            endLineNumber: end.line + 1,
+            endColumn: end.col_utf16 + 1,
+        }
+    }
+}
+
+impl Conv for CompletionItemKind {
+    type Output = return_types::CompletionItemKind;
+
+    fn conv(self) -> <Self as Conv>::Output {
+        use return_types::CompletionItemKind::*;
+        match self {
+            CompletionItemKind::Keyword => Keyword,
+            CompletionItemKind::Snippet => Snippet,
+            CompletionItemKind::Module => Module,
+            CompletionItemKind::Function => Function,
+            CompletionItemKind::Struct => Struct,
+            CompletionItemKind::Enum => Enum,
+            CompletionItemKind::EnumVariant => EnumMember,
+            CompletionItemKind::BuiltinType => Struct,
+            CompletionItemKind::Binding => Variable,
+            CompletionItemKind::Field => Field,
+            CompletionItemKind::Trait => Interface,
+            CompletionItemKind::TypeAlias => Struct,
+            CompletionItemKind::Const => Constant,
+            CompletionItemKind::Static => Value,
+            CompletionItemKind::Method => Method,
+            CompletionItemKind::TypeParam => TypeParameter,
+            CompletionItemKind::Macro => Method,
+        }
+    }
+}