renderError

pub fn renderError(tree: Ast, parse_error: Error, w: *Writer) Writer.Error!void {
    switch (parse_error.tag) {
        .asterisk_after_ptr_deref => {
            // Note that the token will point at the `.*` but ideally the source
            // location would point to the `*` after the `.*`.
            return w.writeAll("'.*' cannot be followed by '*'; are you missing a space?");
        },
        .chained_comparison_operators => {
            return w.writeAll("comparison operators cannot be chained");
        },
        .decl_between_fields => {
            return w.writeAll("declarations are not allowed between container fields");
        },
        .expected_block => {
            return w.print("expected block, found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_block_or_assignment => {
            return w.print("expected block or assignment, found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_block_or_expr => {
            return w.print("expected block or expression, found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_block_or_field => {
            return w.print("expected block or field, found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_container_members => {
            return w.print("expected test, comptime, var decl, or container field, found '{s}'", .{
                tree.tokenTag(parse_error.token).symbol(),
            });
        },
        .expected_expr => {
            return w.print("expected expression, found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_expr_or_assignment => {
            return w.print("expected expression or assignment, found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_expr_or_var_decl => {
            return w.print("expected expression or var decl, found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_fn => {
            return w.print("expected function, found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_inlinable => {
            return w.print("expected 'while' or 'for', found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_labelable => {
            return w.print("expected 'while', 'for', 'inline', or '{{', found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_param_list => {
            return w.print("expected parameter list, found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_prefix_expr => {
            return w.print("expected prefix expression, found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_primary_type_expr => {
            return w.print("expected primary type expression, found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_pub_item => {
            return w.writeAll("expected function or variable declaration after pub");
        },
        .expected_return_type => {
            return w.print("expected return type expression, found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_semi_or_else => {
            return w.writeAll("expected ';' or 'else' after statement");
        },
        .expected_semi_or_lbrace => {
            return w.writeAll("expected ';' or block after function prototype");
        },
        .expected_statement => {
            return w.print("expected statement, found '{s}'", .{
                tree.tokenTag(parse_error.token).symbol(),
            });
        },
        .expected_suffix_op => {
            return w.print("expected pointer dereference, optional unwrap, or field access, found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_type_expr => {
            return w.print("expected type expression, found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_var_decl => {
            return w.print("expected variable declaration, found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_var_decl_or_fn => {
            return w.print("expected variable declaration or function, found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_loop_payload => {
            return w.print("expected loop payload, found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .expected_container => {
            return w.print("expected a struct, enum or union, found '{s}'", .{
                tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev)).symbol(),
            });
        },
        .extern_fn_body => {
            return w.writeAll("extern functions have no body");
        },
        .extra_addrspace_qualifier => {
            return w.writeAll("extra addrspace qualifier");
        },
        .extra_align_qualifier => {
            return w.writeAll("extra align qualifier");
        },
        .extra_allowzero_qualifier => {
            return w.writeAll("extra allowzero qualifier");
        },
        .extra_const_qualifier => {
            return w.writeAll("extra const qualifier");
        },
        .extra_volatile_qualifier => {
            return w.writeAll("extra volatile qualifier");
        },
        .ptr_mod_on_array_child_type => {
            return w.print("pointer modifier '{s}' not allowed on array child type", .{
                tree.tokenTag(parse_error.token).symbol(),
            });
        },
        .invalid_bit_range => {
            return w.writeAll("bit range not allowed on slices and arrays");
        },
        .same_line_doc_comment => {
            return w.writeAll("same line documentation comment");
        },
        .unattached_doc_comment => {
            return w.writeAll("unattached documentation comment");
        },
        .test_doc_comment => {
            return w.writeAll("documentation comments cannot be attached to tests");
        },
        .comptime_doc_comment => {
            return w.writeAll("documentation comments cannot be attached to comptime blocks");
        },
        .varargs_nonfinal => {
            return w.writeAll("function prototype has parameter after varargs");
        },
        .expected_continue_expr => {
            return w.writeAll("expected ':' before while continue expression");
        },

        .expected_semi_after_decl => {
            return w.writeAll("expected ';' after declaration");
        },
        .expected_semi_after_stmt => {
            return w.writeAll("expected ';' after statement");
        },
        .expected_comma_after_field => {
            return w.writeAll("expected ',' after field");
        },
        .expected_comma_after_arg => {
            return w.writeAll("expected ',' after argument");
        },
        .expected_comma_after_param => {
            return w.writeAll("expected ',' after parameter");
        },
        .expected_comma_after_initializer => {
            return w.writeAll("expected ',' after initializer");
        },
        .expected_comma_after_switch_prong => {
            return w.writeAll("expected ',' after switch prong");
        },
        .expected_comma_after_for_operand => {
            return w.writeAll("expected ',' after for operand");
        },
        .expected_comma_after_capture => {
            return w.writeAll("expected ',' after for capture");
        },
        .expected_initializer => {
            return w.writeAll("expected field initializer");
        },
        .mismatched_binary_op_whitespace => {
            return w.print("binary operator '{s}' has whitespace on one side, but not the other", .{tree.tokenTag(parse_error.token).lexeme().?});
        },
        .invalid_ampersand_ampersand => {
            return w.writeAll("ambiguous use of '&&'; use 'and' for logical AND, or change whitespace to ' & &' for bitwise AND");
        },
        .c_style_container => {
            return w.print("'{s} {s}' is invalid", .{
                parse_error.extra.expected_tag.symbol(), tree.tokenSlice(parse_error.token),
            });
        },
        .zig_style_container => {
            return w.print("to declare a container do 'const {s} = {s}'", .{
                tree.tokenSlice(parse_error.token), parse_error.extra.expected_tag.symbol(),
            });
        },
        .previous_field => {
            return w.writeAll("field before declarations here");
        },
        .next_field => {
            return w.writeAll("field after declarations here");
        },
        .expected_var_const => {
            return w.writeAll("expected 'var' or 'const' before variable declaration");
        },
        .wrong_equal_var_decl => {
            return w.writeAll("variable initialized with '==' instead of '='");
        },
        .var_const_decl => {
            return w.writeAll("use 'var' or 'const' to declare variable");
        },
        .extra_for_capture => {
            return w.writeAll("extra capture in for loop");
        },
        .for_input_not_captured => {
            return w.writeAll("for input is not captured");
        },

        .invalid_byte => {
            const tok_slice = tree.source[tree.tokens.items(.start)[parse_error.token]..];
            return w.print("{s} contains invalid byte: '{f}'", .{
                switch (tok_slice[0]) {
                    '\'' => "character literal",
                    '"', '\\' => "string literal",
                    '/' => "comment",
                    else => unreachable,
                },
                std.zig.fmtChar(tok_slice[parse_error.extra.offset]),
            });
        },

        .expected_token => {
            const found_tag = tree.tokenTag(parse_error.token + @intFromBool(parse_error.token_is_prev));
            const expected_symbol = parse_error.extra.expected_tag.symbol();
            switch (found_tag) {
                .invalid => return w.print("expected '{s}', found invalid bytes", .{
                    expected_symbol,
                }),
                else => return w.print("expected '{s}', found '{s}'", .{
                    expected_symbol, found_tag.symbol(),
                }),
            }
        },
    }
}