Commit 755eeb7be0068f8a27aae1d5b8610c6c4da5162d | zig

author	chwayne <39384757+chwayne@users.noreply.github.com> 2021-11-27 04:02:09+00:00
committer	GitHub <noreply@github.com> 2021-11-26 23:02:09-05:00
log	755eeb7be0068f8a27aae1d5b8610c6c4da5162d
tree	8898ae7b7cce932b66164250cb748358af98bde6
parent	fdc04101f343ff090f0c54469a74dc960aa8d904
signature	Signed by PGP key 4AEE18F83AFDEB23

zig fmt: Fix performance issue with nested arrays (#10224)

* Remove double recursive call in renderArrayInit
* Preserve an empty line before a comment line

Fixes #10194

1 files changed, 36 insertions(+), 14 deletions(-)

lib
- std
  - zig
    render.zig

lib/std/zig/render.zig+36-14

...	...	@@ -1747,6 +1747,9 @@ fn renderArrayInit(
1747	1747	var sub_expr_buffer = std.ArrayList(u8).init(gpa);
1748	1748	defer sub_expr_buffer.deinit();
1749	1749
	1750	const sub_expr_buffer_starts = try gpa.alloc(usize, section_exprs.len + 1);
	1751	defer gpa.free(sub_expr_buffer_starts);
	1752
1750	1753	var auto_indenting_stream = Ais{
1751	1754	.indent_delta = indent_delta,
1752	1755	.underlying_writer = sub_expr_buffer.writer(),
...	...	@@ -1757,11 +1760,13 @@ fn renderArrayInit(
1757	1760	var single_line = true;
1758	1761	var contains_newline = false;
1759	1762	for (section_exprs) \|expr, i\| {
1760		sub_expr_buffer.shrinkRetainingCapacity(0);
	1763	const start = sub_expr_buffer.items.len;
	1764	sub_expr_buffer_starts[i] = start;
	1765
1761	1766	if (i + 1 < section_exprs.len) {
1762	1767	try renderExpression(gpa, &auto_indenting_stream, tree, expr, .none);
1763		const width = sub_expr_buffer.items.len;
1764		const this_contains_newline = mem.indexOfScalar(u8, sub_expr_buffer.items, '\n') != null;
	1768	const width = sub_expr_buffer.items.len - start;
	1769	const this_contains_newline = mem.indexOfScalar(u8, sub_expr_buffer.items[start..], '\n') != null;
1765	1770	contains_newline = contains_newline or this_contains_newline;
1766	1771	expr_widths[i] = width;
1767	1772	expr_newlines[i] = this_contains_newline;
...	...	@@ -1779,9 +1784,10 @@ fn renderArrayInit(
1779	1784	column_counter = 0;
1780	1785	}
1781	1786	} else {
1782		try renderExpression(gpa, &auto_indenting_stream, tree, expr, .none);
1783		const width = sub_expr_buffer.items.len;
1784		contains_newline = contains_newline or mem.indexOfScalar(u8, sub_expr_buffer.items, '\n') != null;
	1787	try renderExpression(gpa, &auto_indenting_stream, tree, expr, .comma);
	1788	const width = sub_expr_buffer.items.len - start - 2;
	1789	const this_contains_newline = mem.indexOfScalar(u8, sub_expr_buffer.items[start .. sub_expr_buffer.items.len - 1], '\n') != null;
	1790	contains_newline = contains_newline or this_contains_newline;
1785	1791	expr_widths[i] = width;
1786	1792	expr_newlines[i] = contains_newline;
1787	1793
...	...	@@ -1789,21 +1795,38 @@ fn renderArrayInit(
1789	1795	const column = column_counter % row_size;
1790	1796	column_widths[column] = std.math.max(column_widths[column], width);
1791	1797	}
1792		break;
1793	1798	}
1794	1799	}
	1800	sub_expr_buffer_starts[section_exprs.len] = sub_expr_buffer.items.len;
1795	1801
1796	1802	// Render exprs in current section.
1797	1803	column_counter = 0;
1798		var last_col_index: usize = row_size - 1;
1799	1804	for (section_exprs) \|expr, i\| {
	1805	const start = sub_expr_buffer_starts[i];
	1806	const end = sub_expr_buffer_starts[i + 1];
	1807	const expr_text = sub_expr_buffer.items[start..end];
	1808	if (!expr_newlines[i]) {
	1809	try ais.writer().writeAll(expr_text);
	1810	} else {
	1811	var by_line = std.mem.split(u8, expr_text, "\n");
	1812	var last_line_was_empty = false;
	1813	try ais.writer().writeAll(by_line.next().?);
	1814	while (by_line.next()) \|line\| {
	1815	if (std.mem.startsWith(u8, line, "//") and last_line_was_empty) {
	1816	try ais.insertNewline();
	1817	} else {
	1818	try ais.maybeInsertNewline();
	1819	}
	1820	last_line_was_empty = (line.len == 0);
	1821	try ais.writer().writeAll(line);
	1822	}
	1823	}
	1824
1800	1825	if (i + 1 < section_exprs.len) {
1801	1826	const next_expr = section_exprs[i + 1];
1802		try renderExpression(gpa, ais, tree, expr, .none);
1803
1804	1827	const comma = tree.lastToken(expr) + 1;
1805	1828
1806		if (column_counter != last_col_index) {
	1829	if (column_counter != row_size - 1) {
1807	1830	if (!expr_newlines[i] and !expr_newlines[i + 1]) {
1808	1831	// Neither the current or next expression is multiline
1809	1832	try renderToken(ais, tree, comma, .space); // ,
...	...	@@ -1815,6 +1838,7 @@ fn renderArrayInit(
1815	1838	continue;
1816	1839	}
1817	1840	}
	1841
1818	1842	if (single_line and row_size != 1) {
1819	1843	try renderToken(ais, tree, comma, .space); // ,
1820	1844	continue;
...	...	@@ -1823,8 +1847,6 @@ fn renderArrayInit(
1823	1847	column_counter = 0;
1824	1848	try renderToken(ais, tree, comma, .newline); // ,
1825	1849	try renderExtraNewline(ais, tree, next_expr);
1826		} else {
1827		try renderExpression(gpa, ais, tree, expr, .comma); // ,
1828	1850	}
1829	1851	}
1830	1852
...	...	@@ -2585,7 +2607,7 @@ fn nodeCausesSliceOpSpace(tag: Ast.Node.Tag) bool {
2585	2607	};
2586	2608	}
2587	2609
2588		// Returns the number of nodes in `expr` that are on the same line as `rtoken`.
	2610	// Returns the number of nodes in `exprs` that are on the same line as `rtoken`.
2589	2611	fn rowSize(tree: Ast, exprs: []const Ast.Node.Index, rtoken: Ast.TokenIndex) usize {
2590	2612	const token_tags = tree.tokens.items(.tag);
2591	2613