postcss,(plugins): nanocss, postcss-preset-env

1 files changed, 132 insertions, 0 deletions

diff --git a/node_modules/postcss-normalize-unicode/src/index.js b/node_modules/postcss-normalize-unicode/src/index.js
new file mode 100644
index 00000000..d8a562b8
--- /dev/null
+++ b/node_modules/postcss-normalize-unicode/src/index.js
@@ -0,0 +1,132 @@
+'use strict';
+const browserslist = require('browserslist');
+const valueParser = require('postcss-value-parser');
+
+const regexLowerCaseUPrefix = /^u(?=\+)/;
+
+/**
+ * @param {string} range
+ * @return {string}
+ */
+function unicode(range) {
+  const values = range.slice(2).split('-');
+
+  if (values.length < 2) {
+    return range;
+  }
+
+  const left = values[0].split('');
+  const right = values[1].split('');
+
+  if (left.length !== right.length) {
+    return range;
+  }
+
+  const merged = mergeRangeBounds(left, right);
+
+  if (merged) {
+    return merged;
+  }
+
+  return range;
+}
+/**
+ * @param {string[]} left
+ * @param {string[]} right
+ * @return {false|string}
+ */
+function mergeRangeBounds(left, right) {
+  let questionCounter = 0;
+  let group = 'u+';
+  for (const [index, value] of left.entries()) {
+    if (value === right[index] && questionCounter === 0) {
+      group = group + value;
+    } else if (value === '0' && right[index] === 'f') {
+      questionCounter++;
+      group = group + '?';
+    } else {
+      return false;
+    }
+  }
+  // The maximum number of wildcard characters (?) for ranges is 5.
+  if (questionCounter < 6) {
+    return group;
+  } else {
+    return false;
+  }
+}
+
+/**
+ * IE and Edge before 16 version ignore the unicode-range if the 'U' is lowercase
+ *
+ * https://caniuse.com/#search=unicode-range
+ *
+ * @param {string} browser
+ * @return {boolean}
+ */
+function hasLowerCaseUPrefixBug(browser) {
+  return browserslist('ie <=11, edge <= 15').includes(browser);
+}
+
+/**
+ * @param {string} value
+ * @return {string}
+ */
+function transform(value, isLegacy = false) {
+  return valueParser(value)
+    .walk((child) => {
+      if (child.type === 'unicode-range') {
+        const transformed = unicode(child.value.toLowerCase());
+
+        child.value = isLegacy
+          ? transformed.replace(regexLowerCaseUPrefix, 'U')
+          : transformed;
+      }
+
+      return false;
+    })
+    .toString();
+}
+
+/**
+ * @type {import('postcss').PluginCreator<void>}
+ * @return {import('postcss').Plugin}
+ */
+function pluginCreator() {
+  return {
+    postcssPlugin: 'postcss-normalize-unicode',
+    /** @param {import('postcss').Result & {opts: browserslist.Options}} result*/
+    prepare(result) {
+      const cache = new Map();
+      const resultOpts = result.opts || {};
+      const browsers = browserslist(null, {
+        stats: resultOpts.stats,
+        path: __dirname,
+        env: resultOpts.env,
+      });
+      const isLegacy = browsers.some(hasLowerCaseUPrefixBug);
+
+      return {
+        OnceExit(css) {
+          css.walkDecls(/^unicode-range$/i, (decl) => {
+            const value = decl.value;
+
+            if (cache.has(value)) {
+              decl.value = cache.get(value);
+
+              return;
+            }
+
+            const newValue = transform(value, isLegacy);
+
+            decl.value = newValue;
+            cache.set(value, newValue);
+          });
+        },
+      };
+    },
+  };
+}
+
+pluginCreator.postcss = true;
+module.exports = pluginCreator;