{"id":4528,"date":"2026-09-02T07:30:00","date_gmt":"2026-09-01T22:30:00","guid":{"rendered":"https:\/\/litcoder.com\/?p=4528"},"modified":"2026-08-12T09:36:27","modified_gmt":"2026-08-12T00:36:27","slug":"rust-unittest%eb%a5%bc-%ec%9c%84%ed%95%9c-%ec%9d%98%ec%a1%b4%ec%84%b1-%ea%b2%a9%eb%a6%ac","status":"publish","type":"post","link":"https:\/\/litcoder.com\/?p=4528","title":{"rendered":"Rust unittest\ub97c \uc704\ud55c \uc758\uc874\uc131 \uaca9\ub9ac"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">\ub2e4\ud589\ud788\ub3c4 \uc6b0\ub9ac\ub294 unittest\uc758 \uc720\uc6a9\ud568 \uc798 \uc54c\ub824\uc9c4 \uc2dc\ub300\uc5d0 \uc0b4\uace0 \uc788\uae30\uc5d0 \ub354 \uc774\uc0c1 unittest\ub97c \uc9c0\uc6d0\ud558\ub294 \ud504\ub85c\uadf8\ub798\ubc0d \uc5b8\uc5b4\ub97c \ud2b9\ubcc4\ud558\uac8c \ubc1b\uc544\ub4e4\uc774\uc9c0 \uc54a\ub294\ub2e4. Rust\ub294 \ube44\uad50\uc801 \ucd5c\uc2e0 \uc5b8\uc5b4\uc778 \ub9cc\ud07c \uc774\ub7ec\ud55c \uc694\uad6c\uc0ac\ud56d\ub4e4\uc744 \uc801\uadf9\uc801\uc73c\ub85c \ubc1b\uc544\ub4e4\uc5ec \ubd80\uac00\uc801\uc778 \ud504\ub808\uc784\uc6cc\ud06c\uc758 \ub3c4\uc6c0 \uc5c6\uc774\ub3c4 \uc5b8\uc5b4 \uc790\uccb4\uc5d0\uc11c \uae30\ubcf8\uc801\uc778 unittest\uac00 \uc798 \uc9c0\uc6d0\ub41c\ub2e4.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\ub2e4\ub9cc, Rust\ub294 \uc0c1\uc18d\uc744 \uc9c0\uc6d0\ud558\uc9c0 \uc54a\uae30 \ub54c\ubb38\uc5d0 Python, Java, C++ \uac19\uc740 \uac1d\uccb4\uc9c0\ud5a5 \uc5b8\uc5b4\uc5d0\uc11c \uc758\uc874\uc131\uc744 \uaca9\ub9ac \ud560 \ub54c \uc0ac\uc6a9\ub418\ub294 method overriding\uc774\ub098 object patching\uc744 \uc0ac\uc6a9\ud560 \uc218\ub294 \uc5c6\ub2e4. \uc77c\ubc18\uc801\uc778 \ubc29\ubc95\uc73c\ub85c mock injection\uc744 \uc218\ud589\ud560 \uc218 \uc5c6\ub2e4\uba74 \ub9e4\ubc88 \ubaa8\ub4e0 \uc758\uc874\uc131\uc744 \ubb3c\ub824 \ub193\uace0 test\ub97c \uc218\ud589\ud574\uc57c\ub9cc \ud560\uae4c?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\ub2e4\ud589\ud788\ub3c4 pytest\uc758 mocker patch \ub9cc\ud07c \uc720\uc5f0\ud558\uac8c\ub294 \uc544\ub2c8\uc9c0\ub9cc, Rust\uc5d0\uc11c\ub3c4 trait + automock\uc758 \uc870\ud569\uc73c\ub85c \uc758\uc874\uc131\uc744 \uaca9\ub9ac\ud574\uc11c unittest\ub97c \uc791\uc131\ud560 \uc218 \uc788\ub2e4.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Trait<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Trait\uc740 \uac1d\uccb4\uac04\uc758 \uacc4\uc57d\uc744 \uc815\uc758\ud55c\ub2e4\ub294 \uc810\uc5d0\uc11c \ub2e4\ub978 \uc5b8\uc5b4\uc758 interface\uc640 \ub2ee\uc740 \uc810\uc774 \ub9ce\ub2e4. \uc608\ub97c \ub4e4\uc5b4 \ub370\uc774\ud130 \ubca0\uc774\uc2a4\uc5d0 \uc811\uadfc\ud574\uc11c \uacc4\uc88c\uc758 \uc794\uace0\ub97c \ud655\uc778\ud558\uace0 \uc5c5\ub370\uc774\ud2b8\ud558\ub294 \ub2e4\uc74c\uacfc \uac19\uc740 \uac04\ub2e8\ud55c Database trait\uc744 \uc0dd\uac01\ud574 \ubcf4\uc790.<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"rust\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">pub trait Database {\n    \/\/ \uc0ac\uc6a9\uc790\uc758 \uc794\uace0\ub97c \ubc18\ud658, \uc624\ub958\uac00 \ubc1c\uc0dd\ud558\uba74 \uc5d0\ub7ec \uba54\uc138\uc9c0 \ubc18\ud658.\n    fn get_user_balance(&amp;self, user_id: u64) -> Result&lt;u64, String>;\n\n    \/\/ \uc0ac\uc6a9\uc790\uc758 \uc794\uace0\ub97c amount\ub85c \uc5c5\ub370\uc774\ud2b8.\n    fn update_user_balance(&amp;mut self, user_id: u64, amount: u64) -> Result&lt;(), String>;\n}<\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\uc6b0\ub9ac\ub294 \uc2e4\uc81c \uad6c\ud604\uc774 \uc5c6\ub294 \uc774 trait\uc744 \uc774\uc6a9\ud574\uc11c unittest\ub97c \uc704\ud55c mock inject\uc744 \uc218\ud589\ud560 \uac83\uc774\ub2e4. \uc989, \uc774 trait\uc744 \ubc1b\uc544\ub4e4\uc774\ub294 &#8220;\uc0ac\uc6a9\uc790&#8221;\ub97c \uc815\uc758\ud55c \ub2e4\uc74c, \ud14c\uc2a4\ud2b8\ub97c \uc704\ud574\uc11c\ub294 mock\uc73c\ub85c \uad6c\uc131\ub41c \uac1d\uccb4\ub97c \ub118\uaca8\uc8fc\uc5b4\uc11c \ud14c\uc2a4\ud2b8\ub97c \uc218\ud589\ud558\uace0, \uc2e4\uc81c\ub85c Database trait\uc744 \uc815\uc758\ud558\ub294 \ud504\ub85c\ub355\uc158 \ucf54\ub4dc\ub294 \ub098\uc911\uc5d0 \uc815\uc758\ud574\uc11c \ub118\uaca8\uc8fc\ub824\ub294 \uac83\uc774\ub2e4.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">WalletService &#8211; Database Trait \uc0ac\uc6a9\uc790<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\uc774 trait\uc744 \ubc1b\uc544\ub4e4\uc774\ub294 &#8220;\uc0ac\uc6a9\uc790&#8221;\uc778 <code>WalletService<\/code>\uac1d\uccb4\ub294 \uc774 database trait\uc5d0 interface\ub97c \ud1b5\ud574 \uc811\uadfc\ud558\uac8c \ub41c\ub2e4. \ub2e4\uc74c\uc758 \ucf54\ub4dc\uc5d0\uc11c \ucc98\ub7fc \ucd9c\uae08 \uae30\ub2a5 \uad6c\ud604\uc744 \uc704\ud574 database\ub97c \uc811\uadfc\ud55c\ub2e4.<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"rust\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">pub struct WalletService&lt;DB: Database> {\n    db: DB,\n}\n\nimpl&lt;DB: Database> WalletService&lt;DB> {\n    pub fn new(db: DB) -> Self {\n        Self { db }\n    }\n    \/\/ \ucd9c\uae08\n    pub fn withdraw(&amp;mut self, user_id: u64, amount: u64) -> Result&lt;u64, String> {\n        let current_balance = self.db.get_user_balance(user_id)?;\n        if current_balance &lt; amount {\n            return Err(String::from(\"\uc794\uc561\uc774 \ubd80\uc871\ud569\ub2c8\ub2e4.\"));\n        }\n        let new_balance = current_balance - amount;\n        self.db.update_user_balance(user_id, new_balance)?;\n        Ok(new_balance)\n    }\n}<\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><code><code data-enlighter-language=\"rust\" class=\"EnlighterJSRAW\">fn new(db: DB)<\/code><\/code>\uc5d0\uc11c \uc815\uc758\ub41c \uac83 \ucc98\ub7fc, \uc774 \uac1d\uccb4\ub294 Database trait\uc744 \uad6c\ud604\ud558\ub294 \ubaa8\ub4e0 \uac1d\uccb4\ub97c \ubc1b\uc744 \uc218 \uc788\ub2e4. \uc774\uc81c \uc6b0\ub9ac\ub294 Database trait\uc744 \uad6c\ud604\ud558\ub294 mock \uac1d\uccb4\ub97c \uc774 \ud568\uc218\uc5d0 \ub118\uaca8\uc8fc\uba74 \ub41c\ub2e4.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Mockall Crate &#8211; Automock<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\uc6b0\ub9ac\uac00 WalletService\uc758 database \uc811\uadfc\uc5d0 \ub300\ud55c \ub3d9\uc791\uc744 \ud14c\uc2a4\ud2b8\ud558\uae30 \uc704\ud574 \uc9c1\uc811 Database trait\uc744 \uad6c\ud604\ud558\ub294 mock \uac1d\uccb4\ub97c \uad6c\ud604\ud560 \uc218\ub3c4 \uc788\uaca0\uc9c0\ub9cc, Mockall crate\uc758 Automock\uc740 \uc774 \uacfc\uc815\uc744 \ud3b8\ub9ac\ud558\uac8c \uc218\ud589\ud560 \uc218 \uc788\ub3c4\ub85d \ub3c4\uc640 \uc900\ub2e4.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\uba3c\uc800 Mockall crate\uc744 \uc758\uc874\uc131 \ubaa9\ub85d\uc5d0 \ucd94\uac00\ud574 \uc900\ub2e4.<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"bash\" data-enlighter-theme=\"dracula\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"false\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">cargo add mockall<\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\uc55e\uc11c \ub9cc\ub4e4\uc5c8\ub358 Database trait\uc5d0 unittest \ud658\uacbd\uc5d0\uc11c\ub9cc mock \uac1d\uccb4\ub97c \uc0dd\uc131\ud558\ub3c4\ub85d <code><code data-enlighter-language=\"rust\" class=\"EnlighterJSRAW\">#[cfg_attr(test, automock)]<\/code><\/code> \ub9e4\ud06c\ub85c\ub97c \uc120\uc5b8\ud574\uc900\ub2e4.<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"rust\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">use mockall::automock;\n\n\n#[cfg_attr(test, automock)]\npub trait Database {\n    \/\/ \uc0ac\uc6a9\uc790\uc758 \uc794\uace0\ub97c \ubc18\ud658, \uc624\ub958\uac00 \ubc1c\uc0dd\ud558\uba74 \uc5d0\ub7ec \uba54\uc138\uc9c0 \ubc18\ud658.\n    fn get_user_balance(&amp;self, user_id: u64) -> Result&lt;u64, String>;\n\n    \/\/ \uc0ac\uc6a9\uc790\uc758 \uc794\uace0\ub97c amount\ub85c \uc5c5\ub370\uc774\ud2b8.\n    fn update_user_balance(&amp;mut self, user_id: u64, amount: u64) -> Result&lt;(), String>;\n}<\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">Mock Object\ub97c \uc774\uc6a9\ud55c Unittest\uc791\uc131<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\uba3c\uc800 \ucd9c\uae08\uc744 \uc2dc\ub3c4 \ud560 \ub54c, \uc608\uae08 \uc870\ud68c\uc5d0\uc11c \ucda9\ubd84\ud55c \uae08\uc561\uc774 \ubc18\ud658\ub418\uc5b4 \uc131\uacf5\ud558\ub294 \uacbd\uc6b0\ub97c \ud14c\uc2a4\ud2b8 \ud574\ubcf4\uc790.<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"rust\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"true\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">#[test]\nfn test_withdraw_success() {\n    \/\/ mockall\uc774 \uc790\ub3d9 \uc0dd\uc131\ud55c MockDatabase \uad6c\uc870\uccb4 \uc0ac\uc6a9\n    let mut mock_db = MockDatabase::new();\n\n    \/\/ Expectation(\uae30\ub300\uce58) \uc124\uc815\n    \/\/ get_user_balance\ub294 \uc778\uc790\ub85c \uc0ac\uc6a9\uc790 id\uc778 1\uc744 \ubc1b\uc544 \uc794\uc561 1000000\uc744 \ubc18\ud658, 1\ubc88 \ud638\ucd9c\ub418\uc5b4\uc57c \ud568.\n    mock_db.expect_get_user_balance()\n        .with(mockall::predicate::eq(1))\n        .times(1)\n        .returning(|_| Ok(1000000));\n\n    \/\/ update_user_balance\ub294 \uc778\uc790\ub85c \uc0ac\uc6a9\uc790 id '1'\uacfc \uc794\uc561 '500000'\uc744 \ubc1b\uc544 \uc131\uacf5(())\uc744 \ubc18\ud658, 1\ubc88 \ud638\ucd9c\ub418\uc5b4\uc57c \ud568.\n    mock_db.expect_update_user_balance()\n        .with(mockall::predicate::eq(1), mockall::predicate::eq(500000))\n        .times(1)\n        .returning(|_, _| Ok(()));\n\n    \/\/ Database trait \uc0ac\uc6a9\uc790\uc778 WalletService\uc5d0 mock injection\n    let mut service = WalletService::new(mock_db);\n\n    \/\/ \uc2e4\ud589 \ubc0f \uac80\uc99d\n    let result = service.withdraw(1, 500000);\n    assert!(result.is_ok());\n    assert_eq!(result.unwrap(), 500000);\n}<\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">4\ubc88\uc9f8 \uc904\uc744 \ubcf4\uba74 <code>MockDatabase::new()<\/code>\ub85c Database trait\uc758 mock \uac1d\uccb4\ub97c \uc0dd\uc131\ud558\ub294\ub370, \uc774\ub807\uac8c \uc0dd\uc131\ub41c \uac1d\uccb4\ub294 <strong>automock<\/strong> \ub355\ubd84\uc5d0 \uc5b4\ub5a4 \ud568\uc218\uac00 \uba87 \ubc88 \ud638\ucd9c \ub418\uc5c8\ub294\uc9c0 \uc5ec\ubd80\uc640 \ubc1b\uc740 \uc778\uc790 \uac12 \uac80\uc0ac \uadf8\ub9ac\uace0 \ud574\ub2f9 \ubd88\ub824\uc9c4 \ud568\uc218\uac00 \ubc18\ud658\ud560 \uac12\uc744 \uc9c0\uc815\ud574 \uc8fc\ub294 \ud568\uc218\ub4e4\uc774 \uc790\ub3d9\uc73c\ub85c \ud3ec\ud568\ub41c\ub2e4. \uc704 \ucf54\ub4dc\uc5d0\uc11c 6\ubc88\uc9f8 \uc904\ubd80\ud130 16\ubc88\uc9f8 \uc904\uae4c\uc9c0\uc758 \ub0b4\uc6a9\uc774 \uc774\ub807\uac8c \uc790\ub3d9\uc73c\ub85c \uc0dd\uc131\ub41c mock \uac1d\uccb4\uc5d0\uc11c \uc9c0\uc6d0\ud574 \uc8fc\ub294 \ud568\uc218\ub4e4\uc744 \ud1b5\ud574 expectation\uc744 \uc124\uc815\ud558\ub294 \uc8fc\ub294 \ubd80\ubd84\uc774\ub2e4.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>expect_&lt;\ud568\uc218\uba85&gt;()<\/strong>: trait\uc758 \uba64\ubc84\uc778 \ud568\uc218\uac00 \ud638\ucd9c\ub418\uc9c0 \uc54a\uc73c\uba74 \ud14c\uc2a4\ud2b8\uac00 \uc2e4\ud328\ud55c\ub2e4.<\/li>\n\n\n\n<li><strong>with()<\/strong>: \ud574\ub2f9 \ud568\uc218\uac00 \ud638\ucd9c\ub420 \ub54c \ub118\uaca8\ubc1b\uc740 \uc778\uc790 \uac12\uc744 \ud655\uc778\ud55c\ub2e4.<\/li>\n\n\n\n<li><strong>times()<\/strong>: \ud574\ub2f9 \ud568\uc218\uac00 \ud638\ucd9c \ub41c \ud69f\uc218\ub97c \ud655\uc778\ud55c\ub2e4. \uc774 \uacbd\uc6b0 \ud568\uc218\uac00 \uc815\ud655\ud788 1\ubc88 \ud638\ucd9c\ub418\ub294 \uacbd\uc6b0\uac00 \uc544\ub2c8\ub77c\uba74 \ud14c\uc2a4\ud2b8\uac00 \uc2e4\ud328\ud55c\ub2e4.<\/li>\n\n\n\n<li><strong>returning()<\/strong>: \ud574\ub2f9 \ud568\uc218\uac00 \ubc18\ud658\ud560 \uac12\uc744 \uc9c0\uc815\ud55c\ub2e4.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\uc608\uae08 \ubd80\uc871\uc73c\ub85c \ucd9c\uae08\uc5d0 \uc2e4\ud328\ud558\ub294 \uacbd\uc6b0\ub3c4 \uc791\uc131\ud574 \ubcf4\uc790.<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"rust\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">#[test]\nfn test_withdraw_insufficient_funds() {\n    let mut mock_db = MockDatabase::new();\n\n    \/\/ \uc794\uc561\uc774 \ubd80\uc871\ud55c \uc0c1\ud669 \uc5f0\ucd9c (\ud604\uc7ac \uc794\uc561 300000)\n    mock_db.expect_get_user_balance()\n        .with(mockall::predicate::eq(2))\n        .times(1)\n        .returning(|_| Ok(300000));\n\n    \/\/ \uc794\uc561\uc774 \ubd80\uc871\ud558\ubbc0\ub85c update_user_balance\ub294 \ud638\ucd9c\ub418\uc9c0 \uc54a\uc544\uc57c \ud568 (times(0))\n    mock_db.expect_update_user_balance()\n        .times(0);\n\n    let mut service = WalletService::new(mock_db);\n\n    let result = service.withdraw(2, 500000);\n    assert!(result.is_err());\n    assert_eq!(result.unwrap_err(), \"\uc794\uc561\uc774 \ubd80\uc871\ud569\ub2c8\ub2e4.\");\n}\n<\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">\uc804\uccb4\ucf54\ub4dc<\/h2>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"rust\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">use mockall::automock;\n\n\/\/ \ub370\uc774\ud130\ubca0\uc774\uc2a4 \uc5f0\ub3d9\uc744 \ub2f4\ub2f9\ud558\ub294 Trait\n#[cfg_attr(test, automock)]\npub trait Database {\n    fn get_user_balance(&amp;self, user_id: u64) -> Result&lt;u64, String>;\n    fn update_user_balance(&amp;mut self, user_id: u64, amount: u64) -> Result&lt;(), String>;\n}\n\n\/\/ \ub370\uc774\ud130\ubca0\uc774\uc2a4\ub97c \uc8fc\uc785\ubc1b\uc544 \ube44\uc988\ub2c8\uc2a4 \ub85c\uc9c1\uc744 \uc218\ud589\ud558\ub294 \uc11c\ube44\uc2a4 \uad6c\uc870\uccb4\npub struct WalletService&lt;DB: Database> {\n    db: DB,\n}\n\nimpl&lt;DB: Database> WalletService&lt;DB> {\n    pub fn new(db: DB) -> Self {\n        Self { db }\n    }\n\n    \/\/ \ucd9c\uae08 \ub85c\uc9c1 \uc608\uc2dc\n    pub fn withdraw(&amp;mut self, user_id: u64, amount: u64) -> Result&lt;u64, String> {\n        let current_balance = self.db.get_user_balance(user_id)?;\n\n        if current_balance &lt; amount {\n            return Err(String::from(\"\uc794\uc561\uc774 \ubd80\uc871\ud569\ub2c8\ub2e4.\"));\n        }\n\n        let new_balance = current_balance - amount;\n        self.db.update_user_balance(user_id, new_balance)?;\n\n        Ok(new_balance)\n    }\n}\n\n\/\/ Unittest\n#[cfg(test)]\nmod tests {\n    use super::*;\n\n   #[test]\n    fn test_withdraw_success() {\n        \/\/ mockall\uc774 \uc790\ub3d9 \uc0dd\uc131\ud55c MockDatabase \uad6c\uc870\uccb4 \uc0ac\uc6a9\n        let mut mock_db = MockDatabase::new();\n\n        \/\/ Expectation(\uae30\ub300\uce58) \uc124\uc815\n        \/\/ get_user_balance\ub294 \uc778\uc790\ub85c \uc0ac\uc6a9\uc790 id\uc778 1\uc744 \ubc1b\uc544 \uc794\uc561 1000000\uc744 \ubc18\ud658, 1\ubc88 \ud638\ucd9c\ub418\uc5b4\uc57c \ud568.\n        mock_db.expect_get_user_balance()\n            .with(mockall::predicate::eq(1))\n            .times(1)\n            .returning(|_| Ok(1000000));\n\n        \/\/ update_user_balance\ub294 \uc778\uc790\ub85c \uc0ac\uc6a9\uc790 id '1'\uacfc \uc794\uc561 '500000'\uc744 \ubc1b\uc544 \uc131\uacf5(())\uc744 \ubc18\ud658, 1\ubc88 \ud638\ucd9c\ub418\uc5b4\uc57c \ud568.\n        mock_db.expect_update_user_balance()\n            .with(mockall::predicate::eq(1), mockall::predicate::eq(500000))\n            .times(1)\n            .returning(|_, _| Ok(()));\n\n        \/\/ Database trait \uc0ac\uc6a9\uc790\uc778 WalletService\uc5d0 mock injection\n        let mut service = WalletService::new(mock_db);\n\n        \/\/ \uc2e4\ud589 \ubc0f \uac80\uc99d\n        let result = service.withdraw(1, 500000);\n        assert!(result.is_ok());\n        assert_eq!(result.unwrap(), 500000);\n    }\n\n    #[test]\n    fn test_withdraw_insufficient_funds() {\n        let mut mock_db = MockDatabase::new();\n\n        \/\/ \uc794\uc561\uc774 \ubd80\uc871\ud55c \uc0c1\ud669 \uc5f0\ucd9c (\ud604\uc7ac \uc794\uc561 300000)\n        mock_db.expect_get_user_balance()\n            .with(mockall::predicate::eq(2))\n            .times(1)\n            .returning(|_| Ok(300000));\n\n        \/\/ \uc794\uc561\uc774 \ubd80\uc871\ud558\ubbc0\ub85c update_user_balance\ub294 \ud638\ucd9c\ub418\uc9c0 \uc54a\uc544\uc57c \ud568 (times(0))\n        mock_db.expect_update_user_balance()\n            .times(0);\n\n        let mut service = WalletService::new(mock_db);\n\n        let result = service.withdraw(2, 500000);\n        assert!(result.is_err());\n        assert_eq!(result.unwrap_err(), \"\uc794\uc561\uc774 \ubd80\uc871\ud569\ub2c8\ub2e4.\");\n    }\n}<\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">\uacb0\ub860<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\ucf04\ud2b8 \ubca1\uc758 TDD \uc785\ubb38\uc11c\uc778 &#8220;<a href=\"https:\/\/www.nl.go.kr\/seoji\/contents\/S80100000000.do?schM=intgr_detail_view_isbn&amp;page=1&amp;pageUnit=10&amp;schType=simple&amp;schStr=9788991268043&amp;isbn=8991268048&amp;cipId=37637807%2C2053952\" data-type=\"link\" data-id=\"https:\/\/www.nl.go.kr\/seoji\/contents\/S80100000000.do?schM=intgr_detail_view_isbn&amp;page=1&amp;pageUnit=10&amp;schType=simple&amp;schStr=9788991268043&amp;isbn=8991268048&amp;cipId=37637807%2C2053952\">\ud14c\uc2a4\ud2b8 \uc8fc\ub3c4 \uac1c\ubc1c<\/a>&#8220;\uc744 \ub9c9 \uc77d\uace0\ub098\uc11c \uc774\uac83\uc744 \ub0b4 \uac1c\ubc1c \uaddc\uce59\uc5d0 \ub3c4\uc785\ud558\ub824\uace0 \ub178\ub825\ud558\ub358 \ucd08\uae30\uc5d0  <a href=\"https:\/\/google.github.io\/googletest\/gmock_for_dummies.html\" data-type=\"link\" data-id=\"https:\/\/google.github.io\/googletest\/gmock_for_dummies.html\">gmock<\/a>\uc5d0\uc11c \uc81c\uacf5\ud55c\ub2e4\ub294 \ud568\uc218 \ud638\ucd9c \ud69f\uc218\ub97c \uac80\uc0ac\ud558\ub294 \uae30\ub2a5\uc744 \ubd24\uc744 \ub54c\ub294 &#8220;\uc774\uac8c \uc720\uc6a9\ud558\uae30\ub294 \ud560\uae4c?&#8221; \ud558\ub294 \uc758\uad6c\uc2ec\uc744 \uac00\uc84c\ub358 \uc801\uc774 \uc788\uc5c8\ub2e4. \uadf8 \uc774\ud6c4\ub85c \uc774 \uae30\ub2a5\uc774 mock injection\uc744 \ud560 \ub54c caller\uc758 expectation\uc744 \uc810\uac80\ud558\ub294 \ubb34\ucc99 \uc720\uc6a9\ud560 \uae30\ub2a5\uc774\ub77c\ub294 \uac83\uc744 \uae68\ub2eb\uac8c \ub418\uba74\uc11c Java\uc758 unittest\uc5d0\uc11c\ub3c4 mockito\ub97c \uc120\ud638\ud558\uac8c \ub418\uc5c8\ub294\ub370,  Rust\uc5d0\uc11c\ub3c4 \uc774\ub7ec\ud55c \uae30\ub2a5\uc744 \uc81c\uacf5\ud558\ub294 crate\uc774 \uc788\ub2e4\ub294 \uc810\uc774 \ubb34\ucc99 \ub2e4\ud589\uc2a4\ub7fd\ub2e4.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\ub77c\uc774\ube0c\ub7ec\ub9ac \ud655\uc7a5 \uae30\ub2a5\uc774 Rust\uc5d0\uc11c \ucc98\uc74c \ub3c4\uc785\ub41c\uac83\ub3c4 \uc720\uc77c\ud55c \uac83\ub3c4 \uc544\ub2c8\uc9c0\ub9cc, \ud604\ub300 \ud504\ub85c\uadf8\ub798\ubc0d \uc5b8\uc5b4\uac00 \uc9c0\ud5a5\ud558\ub294 \ubc14\ub97c \uc801\uadf9\uc801\uc73c\ub85c \ubc1b\uc544\ub4e4\uc774\uba74\uc11c\ub3c4 \uace0\uc131\ub2a5\uc744 \uc720\uc9c0\ud558\ub294 Rust\uac00 \uc810\uc810 \ub354 \ub9e4\ub825\uc788\uac8c \ub290\uaef4\uc9c4\ub2e4.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\ub2e4\ud589\ud788\ub3c4 \uc6b0\ub9ac\ub294 unittest\uc758 \uc720\uc6a9\ud568 \uc798 \uc54c\ub824\uc9c4 \uc2dc\ub300\uc5d0 \uc0b4\uace0 \uc788\uae30\uc5d0 \ub354 \uc774\uc0c1 unittest\ub97c \uc9c0\uc6d0\ud558\ub294 \ud504\ub85c\uadf8\ub798\ubc0d \uc5b8\uc5b4\ub97c \ud2b9\ubcc4\ud558\uac8c \ubc1b\uc544\ub4e4\uc774\uc9c0 \uc54a\ub294\ub2e4. Rust\ub294 \ube44\uad50\uc801 \ucd5c\uc2e0 \uc5b8\uc5b4\uc778 \ub9cc\ud07c \uc774\ub7ec\ud55c \uc694\uad6c\uc0ac\ud56d\ub4e4\uc744 \uc801\uadf9\uc801\uc73c\ub85c \ubc1b\uc544\ub4e4\uc5ec \ubd80\uac00\uc801\uc778 \ud504\ub808\uc784\uc6cc\ud06c\uc758 \ub3c4\uc6c0 \uc5c6\uc774\ub3c4 \uc5b8\uc5b4 \uc790\uccb4\uc5d0\uc11c \uae30\ubcf8\uc801\uc778 unittest\uac00 \uc798 \uc9c0\uc6d0\ub41c\ub2e4. \ub2e4\ub9cc, Rust\ub294 \uc0c1\uc18d\uc744 \uc9c0\uc6d0\ud558\uc9c0 \uc54a\uae30 \ub54c\ubb38\uc5d0 Python, Java, C++ \uac19\uc740 \uac1d\uccb4\uc9c0\ud5a5 \uc5b8\uc5b4\uc5d0\uc11c \uc758\uc874\uc131\uc744 \uaca9\ub9ac \ud560 \ub54c \uc0ac\uc6a9\ub418\ub294 method [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":false},"categories":[5],"tags":[33,475,423,293],"class_list":["post-4528","post","type-post","status-publish","format-standard","hentry","category-programming","tag-database","tag-mocking","tag-rust","tag-unittest"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/litcoder.com\/index.php?rest_route=\/wp\/v2\/posts\/4528","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/litcoder.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/litcoder.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/litcoder.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/litcoder.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=4528"}],"version-history":[{"count":20,"href":"https:\/\/litcoder.com\/index.php?rest_route=\/wp\/v2\/posts\/4528\/revisions"}],"predecessor-version":[{"id":4706,"href":"https:\/\/litcoder.com\/index.php?rest_route=\/wp\/v2\/posts\/4528\/revisions\/4706"}],"wp:attachment":[{"href":"https:\/\/litcoder.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4528"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/litcoder.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=4528"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/litcoder.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=4528"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}