From a2de5bf2e68ee591bc10ca5bd6e9dc5282890299 Mon Sep 17 00:00:00 2001
From: Techatrix <19954306+Techatrix@users.noreply.github.com>
Date: Tue, 30 May 2023 00:52:16 +0200
Subject: [PATCH] add `paramSlice` helper function

---
 src/ast.zig                     |  9 +++++++++
 src/features/completions.zig    |  5 +----
 src/features/hover.zig          |  7 +------
 src/features/signature_help.zig | 28 ++--------------------------
 4 files changed, 13 insertions(+), 36 deletions(-)

diff --git a/src/ast.zig b/src/ast.zig
index faa9c2d..6d9be3f 100644
--- a/src/ast.zig
+++ b/src/ast.zig
@@ -991,6 +991,15 @@ pub fn paramLastToken(tree: Ast, param: Ast.full.FnProto.Param) Ast.TokenIndex {
     return param.anytype_ellipsis3 orelse tree.lastToken(param.type_expr);
 }
 
+pub fn paramSlice(tree: Ast, param: Ast.full.FnProto.Param) []const u8 {
+    const first_token = paramFirstToken(tree, param);
+    const last_token = paramLastToken(tree, param);
+
+    const start = offsets.tokenToIndex(tree, first_token);
+    const end = offsets.tokenToLoc(tree, last_token).end;
+    return tree.source[start..end];
+}
+
 pub fn isContainer(tree: Ast, node: Ast.Node.Index) bool {
     return switch (tree.nodes.items(.tag)[node]) {
         .container_decl,
diff --git a/src/features/completions.zig b/src/features/completions.zig
index 3f15e90..fff1751 100644
--- a/src/features/completions.zig
+++ b/src/features/completions.zig
@@ -370,14 +370,11 @@ fn declToCompletion(context: DeclToCompletionContext, decl_handle: Analyser.Decl
                     try Analyser.collectDocComments(allocator, tree, doc_comments, doc_kind, false),
             } } else null;
 
-            const first_token = ast.paramFirstToken(tree, param);
-            const last_token = ast.paramLastToken(tree, param);
-
             try context.completions.append(allocator, .{
                 .label = tree.tokenSlice(param.name_token.?),
                 .kind = .Constant,
                 .documentation = doc,
-                .detail = tree.source[offsets.tokenToIndex(tree, first_token)..offsets.tokenToLoc(tree, last_token).end],
+                .detail = ast.paramSlice(tree, param),
                 .insertText = tree.tokenSlice(param.name_token.?),
                 .insertTextFormat = .PlainText,
             });
diff --git a/src/features/hover.zig b/src/features/hover.zig
index ddbedf2..25a8d2a 100644
--- a/src/features/hover.zig
+++ b/src/features/hover.zig
@@ -48,12 +48,7 @@ pub fn hoverSymbol(server: *Server, decl_handle: Analyser.DeclWithHandle, markup
                 doc_str = try Analyser.collectDocComments(server.arena.allocator(), handle.tree, doc_comments, markup_kind, false);
             }
 
-            const first_token = ast.paramFirstToken(tree, param);
-            const last_token = ast.paramLastToken(tree, param);
-
-            const start = offsets.tokenToIndex(tree, first_token);
-            const end = offsets.tokenToLoc(tree, last_token).end;
-            break :def tree.source[start..end];
+            break :def ast.paramSlice(tree, param);
         },
         .pointer_payload,
         .array_payload,
diff --git a/src/features/signature_help.zig b/src/features/signature_help.zig
index 22679e9..4e3e0ba 100644
--- a/src/features/signature_help.zig
+++ b/src/features/signature_help.zig
@@ -7,12 +7,12 @@ const DocumentStore = @import("../DocumentStore.zig");
 const types = @import("../lsp.zig");
 const Server = @import("../Server.zig");
 const ast = @import("../ast.zig");
+const offsets = @import("../offsets.zig");
 
 const data = @import("../data/data.zig");
 
 fn fnProtoToSignatureInfo(analyser: *Analyser, alloc: std.mem.Allocator, commas: u32, skip_self_param: bool, handle: *const DocumentStore.Handle, fn_node: Ast.Node.Index, proto: Ast.full.FnProto) !types.SignatureInformation {
     const tree = handle.tree;
-    const token_starts = tree.tokens.items(.start);
     const label = Analyser.getFunctionSignature(tree, proto);
     const proto_comments = (try Analyser.getDocComments(alloc, tree, fn_node, .markdown)) orelse "";
 
@@ -29,32 +29,8 @@ fn fnProtoToSignatureInfo(analyser: *Analyser, alloc: std.mem.Allocator, commas:
         else
             "";
 
-        var param_label_start: usize = 0;
-        var param_label_end: usize = 0;
-        if (param.comptime_noalias) |cn| {
-            param_label_start = token_starts[cn];
-            param_label_end = param_label_start + tree.tokenSlice(cn).len;
-        }
-        if (param.name_token) |nt| {
-            if (param_label_start == 0)
-                param_label_start = token_starts[nt];
-            param_label_end = token_starts[nt] + tree.tokenSlice(nt).len;
-        }
-        if (param.anytype_ellipsis3) |ae| {
-            if (param_label_start == 0)
-                param_label_start = token_starts[ae];
-            param_label_end = token_starts[ae] + tree.tokenSlice(ae).len;
-        }
-        if (param.type_expr != 0) {
-            if (param_label_start == 0)
-                param_label_start = token_starts[tree.firstToken(param.type_expr)];
-
-            const last_param_tok = ast.lastToken(tree, param.type_expr);
-            param_label_end = token_starts[last_param_tok] + tree.tokenSlice(last_param_tok).len;
-        }
-        const param_label = tree.source[param_label_start..param_label_end];
         try params.append(alloc, .{
-            .label = .{ .string = param_label },
+            .label = .{ .string = ast.paramSlice(tree, param) },
             .documentation = .{ .MarkupContent = .{
                 .kind = .markdown,
                 .value = param_comments,