const std = @import("std");
/// A string contained in quotes will not be changed in any form.
quotes: []const u8,
/// This character is used to escape in strings.
escape: ?u8,
/// A delimiter does not need any padding around it.
delimiters: []const u8,
/// Kinds of comments, will be removed in the output.
comments: []const struct { []const u8, []const u8 },
pub const html: @This() = .{
.quotes = "\"'",
.escape = null,
.delimiters = "<>",
.comments = &.{.{ "" }},
};
pub const js: @This() = .{
.quotes = "\"'`",
.escape = '\\',
.delimiters = "+-*,.:;[](){}=&|^",
.comments = &.{ .{ "//", "\n" }, .{ "/*", "*/" } },
};
pub const css: @This() = .{
.quotes = "\"'",
.escape = '\\',
.delimiters = ":;{}",
.comments = &.{.{ "/*", "*/" }},
};
fn skip(comptime source: *[]const u8, comptime len: usize) void {
source.* = (source.*)[len..];
}
fn push(
comptime source: *[]const u8,
comptime target: *[]const u8,
comptime len: usize,
) void {
target.* = target.* ++ (source.*)[0..len];
skip(source, len);
}
pub fn minify(
comptime self: *const @This(),
comptime c: []const u8,
) []const u8 {
@setEvalBranchQuota(c.len * 100);
var content = std.mem.trimStart(u8, c, &std.ascii.whitespace);
var block: []const u8 = "";
while (content.len > 0) {
const had_comment: bool = cmt: {
inline for (self.comments) |comment| {
const start, const end = comment;
if (std.mem.startsWith(u8, content, start)) {
skip(&content, start.len);
skip(&content, if (std.mem.indexOf(u8, content, end)) |l| l + end.len else content.len);
break :cmt true;
}
}
break :cmt false;
};
if (had_comment) {} else if (std.mem.indexOfScalar(u8, self.quotes, content[0])) |_| {
const quote = content[0];
push(&content, &block, 1);
while (content.len > 0) {
if (content[0] == self.escape) {
push(&content, &block, 2);
} else if (content[0] == quote) {
push(&content, &block, 1);
break;
}
push(&content, &block, 1);
}
} else {
push(&content, &block, 1);
}
const was_trimmed = content.len > 0 and std.ascii.isWhitespace(content[0]);
content = std.mem.trimStart(u8, content, &std.ascii.whitespace);
if (was_trimmed and
block.len > 0 and
content.len > 0 and
std.mem.indexOfScalar(u8, self.delimiters, block[block.len - 1]) == null and
std.mem.indexOfScalar(u8, self.delimiters, content[0]) == null)
{
block = block ++ " ";
}
}
return block;
}
test "html" {
const buffer: []const u8 =
\\
\\
\\ Some Title
\\
\\
\\ 123
\\
\\ Hello World!
\\
\\
;
try std.testing.expectEqualStrings(
"Some Title123Hello World!",
comptime html.minify(buffer),
);
}
test "css" {
const buffer: []const u8 =
\\body {
\\ background: #fff;
\\ color: red;
\\}
\\
\\#content:first {
\\ user-select: none;
\\ /* comment */
\\ content: ' ';
\\ padding: 5px 5px;
\\}
;
try std.testing.expectEqualStrings(
"body{background:#fff;color:red;}#content:first{user-select:none;content:' ';padding:5px 5px;}",
comptime css.minify(buffer),
);
}
test "js" {
const buffer: []const u8 =
\\class extends HTMLElement {
\\ // comment here
\\ constructor() {
\\ super();
\\ this.attachShadow({ mode: 'open' });
\\ }
\\
\\ /*
\\ * Mulitline
\\ */
\\ connectedCallback() {
\\ const type = this.getAttribute('type');
\\ const template = document.getElementById(`--${type}`);
\\ const node = document.importNode(template.content, true);
\\ this.shadowRoot.appendChild(node);
\\ }
\\}
;
try std.testing.expectEqualStrings(
"class extends HTMLElement{constructor(){super();this.attachShadow({mode:'open'});}connectedCallback(){const type=this.getAttribute('type');const template=document.getElementById(`--${type}`);const node=document.importNode(template.content,true);this.shadowRoot.appendChild(node);}}",
comptime js.minify(buffer),
);
}