Fix duplicate exports initialization with many exports

packages/babel-helper-module-transforms/src/index.ts

@@ -464,11 +464,8 @@ function buildExportInitializationStatements(
     // We generate init statements (`exports.a = exports.b = ... = void 0`)
     // for every 100 exported names to avoid deeply-nested AST structures.
     const chunkSize = 100;
-    for (
-      let i = 0, uninitializedExportNames = [];
-      i < initStatements.length;
-      i += chunkSize
-    ) {
+    for (let i = 0; i < initStatements.length; i += chunkSize) {
+      let uninitializedExportNames = [];
       for (let j = 0; j < chunkSize && i + j < initStatements.length; j++) {
         const [exportName, initStatement] = initStatements[i + j];
         if (initStatement !== null) {

packages/babel-plugin-transform-modules-commonjs/test/fixtures/regression/many-exports-chunked/input.mjs

@@ -0,0 +1,250 @@
+export const a000 = 0;
+export const a001 = 1;
+export const a002 = 2;
+export const a003 = 3;
+export const a004 = 4;
+export const a005 = 5;
+export const a006 = 6;
+export const a007 = 7;
+export const a008 = 8;
+export const a009 = 9;
+export const a010 = 10;
+export const a011 = 11;
+export const a012 = 12;
+export const a013 = 13;
+export const a014 = 14;
+export const a015 = 15;
+export const a016 = 16;
+export const a017 = 17;
+export const a018 = 18;
+export const a019 = 19;
+export const a020 = 20;
+export const a021 = 21;
+export const a022 = 22;
+export const a023 = 23;
+export const a024 = 24;
+export const a025 = 25;
+export const a026 = 26;
+export const a027 = 27;
+export const a028 = 28;
+export const a029 = 29;
+export const a030 = 30;
+export const a031 = 31;
+export const a032 = 32;
+export const a033 = 33;
+export const a034 = 34;
+export const a035 = 35;
+export const a036 = 36;
+export const a037 = 37;
+export const a038 = 38;
+export const a039 = 39;
+export const a040 = 40;
+export const a041 = 41;
+export const a042 = 42;
+export const a043 = 43;
+export const a044 = 44;
+export const a045 = 45;
+export const a046 = 46;
+export const a047 = 47;
+export const a048 = 48;
+export const a049 = 49;
+export const a050 = 50;
+export const a051 = 51;
+export const a052 = 52;
+export const a053 = 53;
+export const a054 = 54;
+export const a055 = 55;
+export const a056 = 56;
+export const a057 = 57;
+export const a058 = 58;
+export const a059 = 59;
+export const a060 = 60;
+export const a061 = 61;
+export const a062 = 62;
+export const a063 = 63;
+export const a064 = 64;
+export const a065 = 65;
+export const a066 = 66;
+export const a067 = 67;
+export const a068 = 68;
+export const a069 = 69;
+export const a070 = 70;
+export const a071 = 71;
+export const a072 = 72;
+export const a073 = 73;
+export const a074 = 74;
+export const a075 = 75;
+export const a076 = 76;
+export const a077 = 77;
+export const a078 = 78;
+export const a079 = 79;
+export const a080 = 80;
+export const a081 = 81;
+export const a082 = 82;
+export const a083 = 83;
+export const a084 = 84;
+export const a085 = 85;
+export const a086 = 86;
+export const a087 = 87;
+export const a088 = 88;
+export const a089 = 89;
+export const a090 = 90;
+export const a091 = 91;
+export const a092 = 92;
+export const a093 = 93;
+export const a094 = 94;
+export const a095 = 95;
+export const a096 = 96;
+export const a097 = 97;
+export const a098 = 98;
+export const a099 = 99;
+export const a100 = 100;
+export const a101 = 101;
+export const a102 = 102;
+export const a103 = 103;
+export const a104 = 104;
+export const a105 = 105;
+export const a106 = 106;
+export const a107 = 107;
+export const a108 = 108;
+export const a109 = 109;
+export const a110 = 110;
+export const a111 = 111;
+export const a112 = 112;
+export const a113 = 113;
+export const a114 = 114;
+export const a115 = 115;
+export const a116 = 116;
+export const a117 = 117;
+export const a118 = 118;
+export const a119 = 119;
+export const a120 = 120;
+export const a121 = 121;
+export const a122 = 122;
+export const a123 = 123;
+export const a124 = 124;
+export const a125 = 125;
+export const a126 = 126;
+export const a127 = 127;
+export const a128 = 128;
+export const a129 = 129;
+export const a130 = 130;
+export const a131 = 131;
+export const a132 = 132;
+export const a133 = 133;
+export const a134 = 134;
+export const a135 = 135;
+export const a136 = 136;
+export const a137 = 137;
+export const a138 = 138;
+export const a139 = 139;
+export const a140 = 140;
+export const a141 = 141;
+export const a142 = 142;
+export const a143 = 143;
+export const a144 = 144;
+export const a145 = 145;
+export const a146 = 146;
+export const a147 = 147;
+export const a148 = 148;
+export const a149 = 149;
+export const a150 = 150;
+export const a151 = 151;
+export const a152 = 152;
+export const a153 = 153;
+export const a154 = 154;
+export const a155 = 155;
+export const a156 = 156;
+export const a157 = 157;
+export const a158 = 158;
+export const a159 = 159;
+export const a160 = 160;
+export const a161 = 161;
+export const a162 = 162;
+export const a163 = 163;
+export const a164 = 164;
+export const a165 = 165;
+export const a166 = 166;
+export const a167 = 167;
+export const a168 = 168;
+export const a169 = 169;
+export const a170 = 170;
+export const a171 = 171;
+export const a172 = 172;
+export const a173 = 173;
+export const a174 = 174;
+export const a175 = 175;
+export const a176 = 176;
+export const a177 = 177;
+export const a178 = 178;
+export const a179 = 179;
+export const a180 = 180;
+export const a181 = 181;
+export const a182 = 182;
+export const a183 = 183;
+export const a184 = 184;
+export const a185 = 185;
+export const a186 = 186;
+export const a187 = 187;
+export const a188 = 188;
+export const a189 = 189;
+export const a190 = 190;
+export const a191 = 191;
+export const a192 = 192;
+export const a193 = 193;
+export const a194 = 194;
+export const a195 = 195;
+export const a196 = 196;
+export const a197 = 197;
+export const a198 = 198;
+export const a199 = 199;
+export const a200 = 200;
+export const a201 = 201;
+export const a202 = 202;
+export const a203 = 203;
+export const a204 = 204;
+export const a205 = 205;
+export const a206 = 206;
+export const a207 = 207;
+export const a208 = 208;
+export const a209 = 209;
+export const a210 = 210;
+export const a211 = 211;
+export const a212 = 212;
+export const a213 = 213;
+export const a214 = 214;
+export const a215 = 215;
+export const a216 = 216;
+export const a217 = 217;
+export const a218 = 218;
+export const a219 = 219;
+export const a220 = 220;
+export const a221 = 221;
+export const a222 = 222;
+export const a223 = 223;
+export const a224 = 224;
+export const a225 = 225;
+export const a226 = 226;
+export const a227 = 227;
+export const a228 = 228;
+export const a229 = 229;
+export const a230 = 230;
+export const a231 = 231;
+export const a232 = 232;
+export const a233 = 233;
+export const a234 = 234;
+export const a235 = 235;
+export const a236 = 236;
+export const a237 = 237;
+export const a238 = 238;
+export const a239 = 239;
+export const a240 = 240;
+export const a241 = 241;
+export const a242 = 242;
+export const a243 = 243;
+export const a244 = 244;
+export const a245 = 245;
+export const a246 = 246;
+export const a247 = 247;
+export const a248 = 248;
+export const a249 = 249;

packages/babel-plugin-transform-modules-commonjs/test/fixtures/regression/many-exports-chunked/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["transform-modules-commonjs"]
+}