Add erc20 implementation

forum-network/src/classes/erc20.js

@@ -0,0 +1,154 @@
+/**
+ * Note: Copied from openzepplin-contracts/contracts/token/ERC20/ERC20.sol
+ * As of commit d59306b: Improve ERC20.decimals documentation (#3933)
+ * on 2023-02-02
+ * by Ladd Hoffman <laddhoffman@gmail.com>
+ *
+ * @dev Implementation of the {IERC20} interface.
+ *
+ * This implementation is agnostic to the way tokens are created. This means
+ * that a supply mechanism has to be added in a derived contract using {_mint}.
+ * For a generic mechanism see {ERC20PresetMinterPauser}.
+ *
+ * TIP: For a detailed writeup see our guide
+ * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
+ * to implement supply mechanisms].
+ *
+ * The default value of {decimals} is 18. To change this, you should override
+ * this function so it returns a different value.
+ *
+ *
+ * ---
+ *
+ * This Javascript implementation is incomplete. It lacks the following:
+ * - allowance
+ * - transferFrom
+ * - approve
+ * - increaseAllowance
+ * - decreaseAllowance
+ * - _beforeTokenTransfer
+ * - _afterTokenTransfer
+ */
+export class ERC20 {
+  /**
+     * @dev Sets the values for {name} and {symbol}.
+     *
+     * All two of these values are immutable: they can only be set once during
+     * construction.
+     * @param {string} name
+     * @param {string} symbol
+     */
+  constructor(name, symbol) {
+    this.name = name;
+    this.symbol = symbol;
+    this.totalSupply = 0;
+    this.balances = new Map(); // <address, number>
+    this.allowances = new Map(); // <address, number>
+  }
+
+  /**
+     * @dev Returns the number of decimals used to get its user representation.
+     * For example, if `decimals` equals `2`, a balance of `505` tokens should
+     * be displayed to a user as `5.05` (`505 / 10 ** 2`).
+     *
+     * Tokens usually opt for a value of 18, imitating the relationship between
+     * Ether and Wei. This is the default value returned by this function, unless
+     * it's overridden.
+     *
+     * NOTE: This information is only used for _display_ purposes: it in
+     * no way affects any of the arithmetic of the contract, including
+     * {IERC20-balanceOf} and {IERC20-transfer}.
+     */
+  static decimals() {
+    return 18;
+  }
+
+  /**
+     * @dev See {IERC20-balanceOf}.
+     */
+  balanceOf(account) {
+    return this.balances.get(account);
+  }
+
+  /**
+     * @dev See {IERC20-transfer}.
+     *
+     * Emits an {Approval} event indicating the updated allowance. This is not
+     * required by the EIP. See the note at the beginning of {ERC20}.
+     *
+     * NOTE: Does not update the allowance if the current allowance
+     * is the maximum `uint256`.
+     *
+     * Requirements:
+     *
+     * - `from` and `to` cannot be the zero address.
+     * - `from` must have a balance of at least `amount`.
+     * - the caller must have allowance for ``from``'s tokens of at least
+     * `amount`.
+     */
+  transfer(from, to, amount) {
+    if (!from) throw new Error('ERC20: transfer from the zero address');
+    if (!to) throw new Error('ERC20: transfer to the zero address');
+
+    // _beforeTokenTransfer(from, to, amount);
+
+    const fromBalance = this.balances.get(from);
+    if (fromBalance < amount) throw new Error('ERC20: transfer amount exceeds balance');
+    this.balances.set(from, fromBalance - amount);
+    // Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
+    // decrementing then incrementing.
+    this.balances.set(to, this.balances.get(to) + amount);
+
+    // emit Transfer(from, to, amount);
+
+    // _afterTokenTransfer(from, to, amount);
+  }
+
+  /** @dev Creates `amount` tokens and assigns them to `account`, increasing
+     * the total supply.
+     *
+     * Emits a {Transfer} event with `from` set to the zero address.
+     *
+     * Requirements:
+     *
+     * - `account` cannot be the zero address.
+     */
+  mint(account, amount) {
+    if (!account) throw new Error('ERC20: mint to the zero address');
+
+    // _beforeTokenTransfer(address(0), account, amount);
+
+    this.totalSupply += amount;
+    // Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
+    this.balances.set(account, this.balances.get(account) + amount);
+    // emit Transfer(address(0), account, amount);
+
+    // _afterTokenTransfer(address(0), account, amount);
+  }
+
+  /**
+     * @dev Destroys `amount` tokens from `account`, reducing the
+     * total supply.
+     *
+     * Emits a {Transfer} event with `to` set to the zero address.
+     *
+     * Requirements:
+     *
+     * - `account` cannot be the zero address.
+     * - `account` must have at least `amount` tokens.
+     */
+  burn(account, amount) {
+    if (!account) throw new Error('ERC20: burn from the zero address');
+
+    // _beforeTokenTransfer(account, address(0), amount);
+
+    const accountBalance = this.balances.get(account);
+    if (accountBalance < amount) throw new Error('ERC20: burn amount exceeds balance');
+    this.balances.set(account, accountBalance - amount);
+    // Overflow not possible: amount <= accountBalance <= totalSupply.
+    this.totalSupply -= amount;
+    // emit Transfer(address(0), account, amount);
+
+    // _afterTokenTransfer(address(0), account, amount);
+  }
+}

forum-network/src/classes/erc721.js

@@ -9,7 +9,7 @@
  * - Emitting events
  */
 
-export class ERC721 /* is ERC165 */ {
+export class ERC721 {
   constructor(name, symbol) {
     this.name = name;
     this.symbol = symbol;
@@ -59,7 +59,7 @@ export class ERC721 /* is ERC165 */ {
     return owner;
   }
 
-  transferFrom(from, to, tokenId) {
+  transfer(from, to, tokenId) {
     const owner = this.owners.get(tokenId);
     if (owner !== from) {
       throw new Error('ERC721: transfer from incorrect owner');

forum-network/src/classes/forum.js

@@ -84,7 +84,7 @@ export class Forum extends ReputationHolder {
     }
 
     // Transfer ownership of the minted/staked token, from the posts to the post author
-    this.dao.reputation.transferFrom(this.id, post.authorPublicKey, post.tokenId);
+    this.dao.reputation.transfer(this.id, post.authorPublicKey, post.tokenId);
     // const toActor = window?.scene?.findActor((actor) => actor.reputationPublicKey === post.authorPublicKey);
     // const value = this.dao.reputation.valueOf(post.tokenId);
   }

forum-network/src/classes/validation-pool.js

@@ -259,7 +259,7 @@ export class ValidationPool extends ReputationHolder {
       console.log(`sending reward for author stake to forum: ${this.dao.reputation.valueOf(this.tokenId)}`);
 
       // Transfer ownership of the minted token, from the pool to the forum
-      this.dao.reputation.transferFrom(this.id, this.dao.forum.id, this.tokenId);
+      this.dao.reputation.transfer(this.id, this.dao.forum.id, this.tokenId);
       // const value = this.dao.reputation.valueOf(this.tokenId);
       // this.actions.transfer.log(this, this.dao.forum, `(${value})`);