diff --git a/.editorconfig b/.editorconfig
index 900dbe4db..3f08c1a48 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -9,9 +9,6 @@ charset = utf-8
 trim_trailing_whitespace = true
 insert_final_newline = true
 
-[tests/**/**.{disabled,expected}.css]
-insert_final_newline = false
-
 [*.{json,yml}]
 indent_size = 2
 
diff --git a/src/__tests__/api.js b/src/__tests__/api.js
index 54f5db2e1..284421954 100644
--- a/src/__tests__/api.js
+++ b/src/__tests__/api.js
@@ -1,4 +1,3 @@
-import {readFileSync as read} from 'fs';
 import postcss from 'postcss';
 import ava from 'ava';
 import nano from '..';
@@ -20,8 +19,11 @@ ava('can be used as a postcss plugin (2)', pluginMacro, postcss([nano()]));
 ava('can be used as a postcss plugin (3)', pluginMacro, postcss(nano));
 
 ava('can be used as a postcss plugin, with options', t => {
-    const css = read(__dirname + '/fixtures/reduceCalc.fixture.css', 'utf-8');
-    const exp = read(__dirname + '/fixtures/reduceCalc.disabled.css', 'utf-8');
+    const css = `
+    h1 {
+        width: calc(3px * 2 - 1px);
+    }`;
+    const exp = `h1{width:calc(3px * 2 - 1px)}`;
 
     return postcss(nano({calc: false})).process(css).then(result => {
         t.deepEqual(result.css, exp, specName('notTransformCalcProperty'));
diff --git a/src/__tests__/fixtures.js b/src/__tests__/fixtures.js
index 1a34496de..897f88caa 100644
--- a/src/__tests__/fixtures.js
+++ b/src/__tests__/fixtures.js
@@ -1,21 +1,389 @@
-import {readdirSync as directory, readFileSync as file} from 'fs';
-import {join} from 'path';
-import ava from 'ava';
+import test from 'ava';
 import processCss from './_processCss';
-import specName from './util/specName';
 
-const base = join(__dirname, 'fixtures');
+test(
+    'should keep spaces in background repeat',
+    processCss,
+    `h1 {
+        background: url(image.png) no-repeat
+    }`,
+    `h1{background:url(image.png) no-repeat}`
+);
 
-const specs = directory(base).reduce((tests, cssFile) => {
-    const parts = cssFile.split('.');
-    if (!tests[parts[0]]) {
-        tests[parts[0]] = {};
+test(
+    'should handle css mixins',
+    processCss,
+    `paper-card {
+        --paper-card-content: {
+            padding-top: 0;
+        };
+        margin: 0 auto 16px;
+        width: 768px;
+        max-width: calc(100% - 32px);
+    }`,
+    `paper-card{--paper-card-content:{padding-top:0};margin:0 auto 16px;width:768px;max-width:calc(100% - 32px)}`
+);
+
+test(
+    'should handle css mixins (2)',
+    processCss,
+    `paper-card {
+        --paper-card-header: {
+            height: 128px;
+            padding: 0 48px;
+            background: var(--primary-color);
+
+            @apply(--layout-vertical);
+            @apply(--layout-end-justified);
+        };
+        --paper-card-header-color: #FFF;
+        --paper-card-content: {
+            padding: 64px;
+        };
+        --paper-card-actions: {
+            @apply(--layout-horizontal);
+            @apply(--layout-end-justified);
+        };
+        width: 384px;
+    }`,
+    `paper-card{--paper-card-header:{height:128px;padding:0 48px;background:var(--primary-color);@apply(--layout-vertical);@apply(--layout-end-justified)};--paper-card-header-color:#fff;--paper-card-content:{padding:64px};--paper-card-actions:{@apply(--layout-horizontal);@apply(--layout-end-justified)};width:384px}`
+);
+
+test(
+    'should dedupe charset definitions',
+    processCss,
+    `@charset 'utf-8';
+
+    a {
+        display: block;
+    }
+
+    @charset 'utf-8';
+
+    div {
+        font-family: €42;
+    }`,
+    `@charset 'utf-8';a{display:block}div{font-family:€42}`
+);
+
+test(
+    'should dedupe selectors',
+    processCss,
+    `h1, h2 {
+        color: red;
+    }
+
+    h2, h1 {
+        font-weight: 400;
+    }`,
+    `h1,h2{color:red;font-weight:400}`
+);
+
+test(
+    'should dedupe semicolons',
+    processCss,
+    `div {
+        font-weight: 900;;;;
+        color: red;;
+    }`,
+    `div{font-weight:900;color:red}`
+);
+
+test(
+    'should discard duplicate keyframes',
+    processCss,
+    `@keyframes fadeOut {
+        0% {
+            opacity: 1;
+        }
+        100% {
+            opacity: 0;
+        }
+    }
+
+    @keyframes fadeOut {
+        0% {
+            opacity: 1;
+        }
+        100% {
+            opacity: 0;
+        }
+    }
+
+    .fadeOut {
+        animation-name: fadeOut;
+    }`,
+    `@keyframes a{0%{opacity:1}to{opacity:0}}.fadeOut{animation-name:a}`
+);
+
+test(
+    'should handle css variables',
+    processCss,
+    `.Button--action:hover:not(.is-disabled) {
+        background-color: var(--wc-variant-background-light);
+    }`,
+    `.Button--action:hover:not(.is-disabled){background-color:var(--wc-variant-background-light)}`
+);
+
+test(
+    'should handle padding shorthand',
+    processCss,
+    `h1 {
+        padding: 10px 20px 30px 40px;
+    }
+
+    h2 {
+        padding: 10px 20px 30px;
+    }
+
+    h3 {
+        padding: 10px 20px;
+    }
+
+    h4 {
+        padding: 10px;
+    }`,
+    `h1{padding:10px 20px 30px 40px}h2{padding:10px 20px 30px}h3{padding:10px 20px}h4{padding:10px}`
+);
+
+test(
+    'should normalize urls',
+    processCss,
+    `body {
+        background: url("http://somewebsite.com/assets/css/../images/test.jpg");
+    }`,
+    `body{background:url(http://somewebsite.com/assets/images/test.jpg)}`
+);
+
+test(
+    'should optimise gradient colour stops',
+    processCss,
+    `div {
+        background-image: -webkit-linear-gradient(black, green, yellow);
+    }`,
+    `div{background-image:-webkit-linear-gradient(#000,green,#ff0)}`
+);
+
+test(
+    'should not mangle multiple gradients',
+    processCss,
+    `.two-gradients {
+        background: linear-gradient(#fff, #999) no-repeat border-box, linear-gradient(#eee, #777) no-repeat border-box;
+        background-size: 98px 50px, 18px 50px;
+        background-position: 0 0, 98px 0;
+        background-origin: padding-box, padding-box;
+    }`,
+    `.two-gradients{background:linear-gradient(#fff,#999) no-repeat border-box,linear-gradient(#eee,#777) no-repeat border-box;background-size:98px 50px,18px 50px;background-position:0 0,98px 0;background-origin:padding-box,padding-box}`
+);
+
+test(
+    'should optimise border longhand',
+    processCss,
+    `h1 {
+        border-width: 1px 1px 1px 1px;
+        border-color: red #f00 red #f00;
+        border-style: solid solid solid solid;
+    }`,
+    `h1{border:1px solid red}`
+);
+
+test(
+    'should trim whitespace in border radius',
+    processCss,
+    `div {
+        border-radius: 100% / 10%;
+    }`,
+    `div{border-radius:100%/10%}`
+);
+
+test(
+    'should trim whitespace in selector combinators',
+    processCss,
+    `p + p {
+        font-style: italic;
+    }
+
+    h1 ~ p {
+        font-size: 2em;
+    }
+
+    p > a {
+        font-weight: 700;
+    }`,
+    `p+p{font-style:italic}h1~p{font-size:2em}p>a{font-weight:700}`
+);
+
+test(
+    'should trim whitespace in border radius',
+    processCss,
+    `div {
+        border-radius: 100% / 10%;
+    }`,
+    `div{border-radius:100%/10%}`
+);
+
+test(
+    'should optimise duration',
+    processCss,
+    `.short {
+        animation-duration: 200ms;
+    }
+
+    .long {
+        animation-duration: 2s;
+    }
+
+    .negative {
+        animation-duration: -569ms;
+    }`,
+    `.short{animation-duration:.2s}.long{animation-duration:2s}.negative{animation-duration:-569ms}`
+);
+
+test(
+    'should optimise font face',
+    processCss,
+    `@font-face {
+        font-family: Glyphicons Halflings;
+        src: url(../fonts/bootstrap/glyphicons-halflings-regular.eot);
+        src: url(../fonts/bootstrap/glyphicons-halflings-regular.eot?#iefix) format("embedded-opentype"),
+             url(../fonts/bootstrap/glyphicons-halflings-regular.woff2) format("woff2"),
+             url(../fonts/bootstrap/glyphicons-halflings-regular.woff) format("woff"),
+             url(../fonts/bootstrap/glyphicons-halflings-regular.ttf) format("truetype"),
+             url(../fonts/bootstrap/glyphicons-halflings-regular.svg#glyphicons_halflingsregular) format("svg")
+    }
+
+    .icon {
+        font-family: Glyphicons Halflings;
+    }`,
+    `@font-face{font-family:Glyphicons Halflings;src:url(../fonts/bootstrap/glyphicons-halflings-regular.eot);src:url(../fonts/bootstrap/glyphicons-halflings-regular.eot?#iefix) format("embedded-opentype"),url(../fonts/bootstrap/glyphicons-halflings-regular.woff2) format("woff2"),url(../fonts/bootstrap/glyphicons-halflings-regular.woff) format("woff"),url(../fonts/bootstrap/glyphicons-halflings-regular.ttf) format("truetype"),url(../fonts/bootstrap/glyphicons-halflings-regular.svg#glyphicons_halflingsregular) format("svg")}.icon{font-family:Glyphicons Halflings}`
+);
+
+test(
+    'should optimise ie9 hack',
+    processCss,
+    `h1 {
+        margin-top: 10px \\9;
+    }`,
+    `h1{margin-top:10px\\9}`
+);
+
+test(
+    'should optimise !important',
+    processCss,
+    `p {
+        margin: 100px !important;
+    }`,
+    `p{margin:100px!important}`
+);
+
+test(
+    'should optimise margin longhand',
+    processCss,
+    `h1 {
+        margin-top: 9px;
+        margin-right: 10px;
+        margin-bottom: 11px;
+        margin-left: 12px;
+    }`,
+    `h1{margin:9px 10px 11px 12px}`
+);
+
+test(
+    'should optimise margin longhand (2)',
+    processCss,
+    `h1 {
+        margin-top: 9px;
+        margin-right: 10px;
+        margin-bottom: 9px;
+        margin-left: 10px;
+    }`,
+    `h1{margin:9px 10px}`
+);
+
+test(
+    'should optimise margin longhand (3)',
+    processCss,
+    `h1 {
+        margin-top: 8px;
+        margin-right: 12px !important;
+        margin-bottom: 14px;
+        margin-left: 10px !important;
+    }`,
+    `h1{margin-top:8px;margin-right:12px!important;margin-bottom:14px;margin-left:10px!important}`
+);
+
+test(
+    'should optimise margin shorthand',
+    processCss,
+    `h1 {
+        /* No expected optimisation */
+        margin: 10px 20px 30px 40px;
+    }
+
+    h2 {
+        /* Expected to transform to 3 values */
+        margin: 10px 20px 30px 20px;
+    }
+
+    h3 {
+        /* Expected to transform to 2 values */
+        margin: 10px 20px 10px 20px;
+    }
+
+    h4 {
+        /* Expected to transform to 1 value */
+        margin: 10px 10px 10px 10px;
+    }`,
+    `h1{margin:10px 20px 30px 40px}h2{margin:10px 20px 30px}h3{margin:10px 20px}h4{margin:10px}`
+);
+
+test(
+    'should optimise padding longhand',
+    processCss,
+    `div {
+        padding-left: 1px;
+        padding-bottom: 2px;
+        padding-top: 3px;
+        padding-right: 4px;
+    }`,
+    `div{padding:3px 4px 2px 1px}`
+);
+
+test(
+    'should preserve calc spaces',
+    processCss,
+    `div {
+        width: calc(100vw / 2 - 6px + 0);
+    }`,
+    `div{width:calc(100vw / 2 - 6px + 0)}`
+);
+
+test(
+    'should reduce calc',
+    processCss,
+    `h1 {
+        width: calc(3px * 2 - 1px);
+    }`,
+    `h1{width:5px}`
+);
+
+test(
+    'should not reduce calc when disabled',
+    processCss,
+    `h1 {
+        width: calc(3px * 2 - 1px);
+    }`,
+    `h1{width:calc(3px * 2 - 1px)}`,
+    {
+        calc: false,
     }
-    tests[parts[0]][parts[1]] = file(join(base, cssFile), 'utf-8');
-    return tests;
-}, {});
+);
 
-Object.keys(specs).forEach(name => {
-    const {fixture, expected} = specs[name];
-    ava(specName(name), processCss, fixture, expected);
-});
+test(
+    'should optimise svg',
+    processCss,
+    `.box {
+        background-image: url('data:image/svg+xml,%3C%3Fxml%20version%3D%221.0%22%20%3F%3E%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20version%3D%221.1%22%20width%3D%22100%25%22%20height%3D%22100%25%22%20viewBox%3D%220%200%201%201%22%20preserveAspectRatio%3D%22none%22%3E%3ClinearGradient%20id%3D%22gradient%22%20gradientUnits%3D%22userSpaceOnUse%22%20x1%3D%220%25%22%20y1%3D%220%25%22%20x2%3D%22100%25%22%20y2%3D%220%25%22%3E%3Cstop%20offset%3D%220%25%22%20stop-color%3D%22%23414042%22%2F%3E%3Cstop%20offset%3D%22100%25%22%20stop-color%3D%22%23ffffff%22%20stop-opacity%3D%220%22%2F%3E%3C%2FlinearGradient%3E%3Crect%20x%3D%220%22%20y%3D%220%22%20width%3D%221%22%20height%3D%221%22%20fill%3D%22url(%23gradient)%22%20%2F%3E%3C%2Fsvg%3E');
+    }`,
+    `.box{background-image:url("data:image/svg+xml;charset=utf-8,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 1 1' preserveAspectRatio='none'%3E%3ClinearGradient id='a' gradientUnits='userSpaceOnUse' x1='0%25' y1='0%25' y2='0%25'%3E%3Cstop offset='0%25' stop-color='%23414042'/%3E%3Cstop offset='100%25' stop-color='%23fff' stop-opacity='0'/%3E%3C/linearGradient%3E%3Cpath fill='url(%23a)' d='M0 0h1v1H0z'/%3E%3C/svg%3E")}`
+);
diff --git a/src/__tests__/fixtures/backgroundRepeatKeepSpaces.expected.css b/src/__tests__/fixtures/backgroundRepeatKeepSpaces.expected.css
deleted file mode 100644
index bb1afc0c3..000000000
--- a/src/__tests__/fixtures/backgroundRepeatKeepSpaces.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-h1{background:url(image.png) no-repeat}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/backgroundRepeatKeepSpaces.fixture.css b/src/__tests__/fixtures/backgroundRepeatKeepSpaces.fixture.css
deleted file mode 100644
index ddf3b3f67..000000000
--- a/src/__tests__/fixtures/backgroundRepeatKeepSpaces.fixture.css
+++ /dev/null
@@ -1,3 +0,0 @@
-h1 {
-    background: url(image.png) no-repeat
-}
diff --git a/src/__tests__/fixtures/cssMixins.expected.css b/src/__tests__/fixtures/cssMixins.expected.css
deleted file mode 100644
index 1df8e7bbc..000000000
--- a/src/__tests__/fixtures/cssMixins.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-paper-card{--paper-card-content:{padding-top:0};margin:0 auto 16px;width:768px;max-width:calc(100% - 32px)}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/cssMixins.fixture.css b/src/__tests__/fixtures/cssMixins.fixture.css
deleted file mode 100644
index fec11e512..000000000
--- a/src/__tests__/fixtures/cssMixins.fixture.css
+++ /dev/null
@@ -1,8 +0,0 @@
-paper-card {
-    --paper-card-content: {
-        padding-top: 0;
-    };
-    margin: 0 auto 16px;
-    width: 768px;
-    max-width: calc(100% - 32px);
-}
diff --git a/src/__tests__/fixtures/cssMixins2.expected.css b/src/__tests__/fixtures/cssMixins2.expected.css
deleted file mode 100644
index 58fa5f3db..000000000
--- a/src/__tests__/fixtures/cssMixins2.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-paper-card{--paper-card-header:{height:128px;padding:0 48px;background:var(--primary-color);@apply(--layout-vertical);@apply(--layout-end-justified)};--paper-card-header-color:#fff;--paper-card-content:{padding:64px};--paper-card-actions:{@apply(--layout-horizontal);@apply(--layout-end-justified)};width:384px}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/cssMixins2.fixture.css b/src/__tests__/fixtures/cssMixins2.fixture.css
deleted file mode 100644
index 64227c9b0..000000000
--- a/src/__tests__/fixtures/cssMixins2.fixture.css
+++ /dev/null
@@ -1,19 +0,0 @@
-paper-card {
-    --paper-card-header: {
-        height: 128px;
-        padding: 0 48px;
-        background: var(--primary-color);
-
-        @apply(--layout-vertical);
-        @apply(--layout-end-justified);
-    };
-    --paper-card-header-color: #FFF;
-    --paper-card-content: {
-        padding: 64px;
-    };
-    --paper-card-actions: {
-        @apply(--layout-horizontal);
-        @apply(--layout-end-justified);
-    };
-    width: 384px;
-}
diff --git a/src/__tests__/fixtures/dedupeCharset.expected.css b/src/__tests__/fixtures/dedupeCharset.expected.css
deleted file mode 100644
index fee43bbcc..000000000
--- a/src/__tests__/fixtures/dedupeCharset.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-@charset 'utf-8';a{display:block}div{font-family:€42}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/dedupeCharset.fixture.css b/src/__tests__/fixtures/dedupeCharset.fixture.css
deleted file mode 100644
index 02da33832..000000000
--- a/src/__tests__/fixtures/dedupeCharset.fixture.css
+++ /dev/null
@@ -1,11 +0,0 @@
-@charset 'utf-8';
-
-a {
-    display: block;
-}
-
-@charset 'utf-8';
-
-div {
-    font-family: €42;
-}
diff --git a/src/__tests__/fixtures/dedupeSelectors.expected.css b/src/__tests__/fixtures/dedupeSelectors.expected.css
deleted file mode 100644
index d71c63463..000000000
--- a/src/__tests__/fixtures/dedupeSelectors.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-h1,h2{color:red;font-weight:400}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/dedupeSelectors.fixture.css b/src/__tests__/fixtures/dedupeSelectors.fixture.css
deleted file mode 100644
index 5092451d8..000000000
--- a/src/__tests__/fixtures/dedupeSelectors.fixture.css
+++ /dev/null
@@ -1,7 +0,0 @@
-h1, h2 {
-    color: red;
-}
-
-h2, h1 {
-    font-weight: 400;
-}
diff --git a/src/__tests__/fixtures/dedupeSemicolons.expected.css b/src/__tests__/fixtures/dedupeSemicolons.expected.css
deleted file mode 100644
index 60ed870a5..000000000
--- a/src/__tests__/fixtures/dedupeSemicolons.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-div{font-weight:900;color:red}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/dedupeSemicolons.fixture.css b/src/__tests__/fixtures/dedupeSemicolons.fixture.css
deleted file mode 100644
index 32c57ce04..000000000
--- a/src/__tests__/fixtures/dedupeSemicolons.fixture.css
+++ /dev/null
@@ -1,4 +0,0 @@
-div {
-    font-weight: 900;;;;
-    color: red;;
-}
diff --git a/src/__tests__/fixtures/discardDuplicateKeyframes.expected.css b/src/__tests__/fixtures/discardDuplicateKeyframes.expected.css
deleted file mode 100644
index 28fd5aac0..000000000
--- a/src/__tests__/fixtures/discardDuplicateKeyframes.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-@keyframes a{0%{opacity:1}to{opacity:0}}.fadeOut{animation-name:a}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/discardDuplicateKeyframes.fixture.css b/src/__tests__/fixtures/discardDuplicateKeyframes.fixture.css
deleted file mode 100644
index b6994006f..000000000
--- a/src/__tests__/fixtures/discardDuplicateKeyframes.fixture.css
+++ /dev/null
@@ -1,21 +0,0 @@
-@keyframes fadeOut {
-    0% {
-        opacity: 1;
-    }
-    100% {
-        opacity: 0;
-    }
-}
-
-@keyframes fadeOut {
-    0% {
-        opacity: 1;
-    }
-    100% {
-        opacity: 0;
-    }
-}
-
-.fadeOut {
-    animation-name: fadeOut;
-}
diff --git a/src/__tests__/fixtures/handleVars.expected.css b/src/__tests__/fixtures/handleVars.expected.css
deleted file mode 100644
index 5d8106c2b..000000000
--- a/src/__tests__/fixtures/handleVars.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-.Button--action:hover:not(.is-disabled){background-color:var(--wc-variant-background-light)}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/handleVars.fixture.css b/src/__tests__/fixtures/handleVars.fixture.css
deleted file mode 100644
index f2837325f..000000000
--- a/src/__tests__/fixtures/handleVars.fixture.css
+++ /dev/null
@@ -1,3 +0,0 @@
-.Button--action:hover:not(.is-disabled) {
-    background-color: var(--wc-variant-background-light);
-}
diff --git a/src/__tests__/fixtures/keepPaddingShorthand.expected.css b/src/__tests__/fixtures/keepPaddingShorthand.expected.css
deleted file mode 100644
index 1be02de83..000000000
--- a/src/__tests__/fixtures/keepPaddingShorthand.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-h1{padding:10px 20px 30px 40px}h2{padding:10px 20px 30px}h3{padding:10px 20px}h4{padding:10px}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/keepPaddingShorthand.fixture.css b/src/__tests__/fixtures/keepPaddingShorthand.fixture.css
deleted file mode 100644
index 758f354cb..000000000
--- a/src/__tests__/fixtures/keepPaddingShorthand.fixture.css
+++ /dev/null
@@ -1,18 +0,0 @@
-/* Padding values are also run through the shorthand optimiser;
-   this test just ensures that they are not mangled */
-
-h1 {
-    padding: 10px 20px 30px 40px;
-}
-
-h2 {
-    padding: 10px 20px 30px;
-}
-
-h3 {
-    padding: 10px 20px;
-}
-
-h4 {
-    padding: 10px;
-}
diff --git a/src/__tests__/fixtures/normalizeUrl.expected.css b/src/__tests__/fixtures/normalizeUrl.expected.css
deleted file mode 100644
index 0621de12b..000000000
--- a/src/__tests__/fixtures/normalizeUrl.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-body{background:url(http://somewebsite.com/assets/images/test.jpg)}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/normalizeUrl.fixture.css b/src/__tests__/fixtures/normalizeUrl.fixture.css
deleted file mode 100644
index 06d8a89e6..000000000
--- a/src/__tests__/fixtures/normalizeUrl.fixture.css
+++ /dev/null
@@ -1,3 +0,0 @@
-body {
-    background: url("http://somewebsite.com/assets/css/../images/test.jpg");
-}
diff --git a/src/__tests__/fixtures/optimiseBackgroundGradients.expected.css b/src/__tests__/fixtures/optimiseBackgroundGradients.expected.css
deleted file mode 100644
index 178b23696..000000000
--- a/src/__tests__/fixtures/optimiseBackgroundGradients.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-div{background-image:-webkit-linear-gradient(#000,green,#ff0)}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/optimiseBackgroundGradients.fixture.css b/src/__tests__/fixtures/optimiseBackgroundGradients.fixture.css
deleted file mode 100644
index 8c851f573..000000000
--- a/src/__tests__/fixtures/optimiseBackgroundGradients.fixture.css
+++ /dev/null
@@ -1,3 +0,0 @@
-div {
-    background-image: -webkit-linear-gradient(black, green, yellow);
-}
diff --git a/src/__tests__/fixtures/optimiseBackgroundGradients2.expected.css b/src/__tests__/fixtures/optimiseBackgroundGradients2.expected.css
deleted file mode 100644
index 1bd441a7f..000000000
--- a/src/__tests__/fixtures/optimiseBackgroundGradients2.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-.two-gradients{background:linear-gradient(#fff,#999) no-repeat border-box,linear-gradient(#eee,#777) no-repeat border-box;background-size:98px 50px,18px 50px;background-position:0 0,98px 0;background-origin:padding-box,padding-box}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/optimiseBackgroundGradients2.fixture.css b/src/__tests__/fixtures/optimiseBackgroundGradients2.fixture.css
deleted file mode 100644
index f05bc0930..000000000
--- a/src/__tests__/fixtures/optimiseBackgroundGradients2.fixture.css
+++ /dev/null
@@ -1,6 +0,0 @@
-.two-gradients {
-    background: linear-gradient(#fff, #999) no-repeat border-box, linear-gradient(#eee, #777) no-repeat border-box;
-    background-size: 98px 50px, 18px 50px;
-    background-position: 0 0, 98px 0;
-    background-origin: padding-box, padding-box;
-}
diff --git a/src/__tests__/fixtures/optimiseBorderLonghand.expected.css b/src/__tests__/fixtures/optimiseBorderLonghand.expected.css
deleted file mode 100644
index fec84bb40..000000000
--- a/src/__tests__/fixtures/optimiseBorderLonghand.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-h1{border:1px solid red}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/optimiseBorderLonghand.fixture.css b/src/__tests__/fixtures/optimiseBorderLonghand.fixture.css
deleted file mode 100644
index 9c3e29d45..000000000
--- a/src/__tests__/fixtures/optimiseBorderLonghand.fixture.css
+++ /dev/null
@@ -1,5 +0,0 @@
-h1 {
-    border-width: 1px 1px 1px 1px;
-    border-color: red #f00 red #f00;
-    border-style: solid solid solid solid;
-}
diff --git a/src/__tests__/fixtures/optimiseBorderRadius.expected.css b/src/__tests__/fixtures/optimiseBorderRadius.expected.css
deleted file mode 100644
index 6525b7f21..000000000
--- a/src/__tests__/fixtures/optimiseBorderRadius.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-div{border-radius:100%/10%}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/optimiseBorderRadius.fixture.css b/src/__tests__/fixtures/optimiseBorderRadius.fixture.css
deleted file mode 100644
index 3ca89b8af..000000000
--- a/src/__tests__/fixtures/optimiseBorderRadius.fixture.css
+++ /dev/null
@@ -1,3 +0,0 @@
-div {
-    border-radius: 100% / 10%;
-}
diff --git a/src/__tests__/fixtures/optimiseCombinators.expected.css b/src/__tests__/fixtures/optimiseCombinators.expected.css
deleted file mode 100644
index 6c4316d57..000000000
--- a/src/__tests__/fixtures/optimiseCombinators.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-p+p{font-style:italic}h1~p{font-size:2em}p>a{font-weight:700}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/optimiseCombinators.fixture.css b/src/__tests__/fixtures/optimiseCombinators.fixture.css
deleted file mode 100644
index 6072260a5..000000000
--- a/src/__tests__/fixtures/optimiseCombinators.fixture.css
+++ /dev/null
@@ -1,11 +0,0 @@
-p + p {
-    font-style: italic;
-}
-
-h1 ~ p {
-    font-size: 2em;
-}
-
-p > a {
-    font-weight: 700;
-}
diff --git a/src/__tests__/fixtures/optimiseDuration.expected.css b/src/__tests__/fixtures/optimiseDuration.expected.css
deleted file mode 100644
index ed9c440f6..000000000
--- a/src/__tests__/fixtures/optimiseDuration.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-.short{animation-duration:.2s}.long{animation-duration:2s}.negative{animation-duration:-569ms}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/optimiseDuration.fixture.css b/src/__tests__/fixtures/optimiseDuration.fixture.css
deleted file mode 100644
index bbc40418c..000000000
--- a/src/__tests__/fixtures/optimiseDuration.fixture.css
+++ /dev/null
@@ -1,11 +0,0 @@
-.short {
-    animation-duration: 200ms;
-}
-
-.long {
-    animation-duration: 2s;
-}
-
-.negative {
-    animation-duration: -569ms;
-}
diff --git a/src/__tests__/fixtures/optimiseFontFace.expected.css b/src/__tests__/fixtures/optimiseFontFace.expected.css
deleted file mode 100644
index 004e556c0..000000000
--- a/src/__tests__/fixtures/optimiseFontFace.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-@font-face{font-family:Glyphicons Halflings;src:url(../fonts/bootstrap/glyphicons-halflings-regular.eot);src:url(../fonts/bootstrap/glyphicons-halflings-regular.eot?#iefix) format("embedded-opentype"),url(../fonts/bootstrap/glyphicons-halflings-regular.woff2) format("woff2"),url(../fonts/bootstrap/glyphicons-halflings-regular.woff) format("woff"),url(../fonts/bootstrap/glyphicons-halflings-regular.ttf) format("truetype"),url(../fonts/bootstrap/glyphicons-halflings-regular.svg#glyphicons_halflingsregular) format("svg")}.icon{font-family:Glyphicons Halflings}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/optimiseFontFace.fixture.css b/src/__tests__/fixtures/optimiseFontFace.fixture.css
deleted file mode 100644
index 867f73b2f..000000000
--- a/src/__tests__/fixtures/optimiseFontFace.fixture.css
+++ /dev/null
@@ -1,13 +0,0 @@
-@font-face {
-    font-family: Glyphicons Halflings;
-    src: url(../fonts/bootstrap/glyphicons-halflings-regular.eot);
-    src: url(../fonts/bootstrap/glyphicons-halflings-regular.eot?#iefix) format("embedded-opentype"),
-         url(../fonts/bootstrap/glyphicons-halflings-regular.woff2) format("woff2"),
-         url(../fonts/bootstrap/glyphicons-halflings-regular.woff) format("woff"),
-         url(../fonts/bootstrap/glyphicons-halflings-regular.ttf) format("truetype"),
-         url(../fonts/bootstrap/glyphicons-halflings-regular.svg#glyphicons_halflingsregular) format("svg")
-}
-
-.icon {
-    font-family: Glyphicons Halflings;
-}
diff --git a/src/__tests__/fixtures/optimiseIe9Hack.expected.css b/src/__tests__/fixtures/optimiseIe9Hack.expected.css
deleted file mode 100644
index f757a5a63..000000000
--- a/src/__tests__/fixtures/optimiseIe9Hack.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-h1{margin-top:10px\9}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/optimiseIe9Hack.fixture.css b/src/__tests__/fixtures/optimiseIe9Hack.fixture.css
deleted file mode 100644
index cfb2abdc4..000000000
--- a/src/__tests__/fixtures/optimiseIe9Hack.fixture.css
+++ /dev/null
@@ -1,3 +0,0 @@
-h1 {
-    margin-top: 10px \9;
-}
diff --git a/src/__tests__/fixtures/optimiseImportant.expected.css b/src/__tests__/fixtures/optimiseImportant.expected.css
deleted file mode 100644
index cbf3ce009..000000000
--- a/src/__tests__/fixtures/optimiseImportant.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-p{margin:100px!important}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/optimiseImportant.fixture.css b/src/__tests__/fixtures/optimiseImportant.fixture.css
deleted file mode 100644
index 9cdf66510..000000000
--- a/src/__tests__/fixtures/optimiseImportant.fixture.css
+++ /dev/null
@@ -1,3 +0,0 @@
-p {
-    margin: 100px !important;
-}
diff --git a/src/__tests__/fixtures/optimiseMarginLonghand.expected.css b/src/__tests__/fixtures/optimiseMarginLonghand.expected.css
deleted file mode 100644
index 49bbdd99e..000000000
--- a/src/__tests__/fixtures/optimiseMarginLonghand.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-h1{margin:9px 10px 11px 12px}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/optimiseMarginLonghand.fixture.css b/src/__tests__/fixtures/optimiseMarginLonghand.fixture.css
deleted file mode 100644
index cb4ed8250..000000000
--- a/src/__tests__/fixtures/optimiseMarginLonghand.fixture.css
+++ /dev/null
@@ -1,6 +0,0 @@
-h1 {
-    margin-top: 9px;
-    margin-right: 10px;
-    margin-bottom: 11px;
-    margin-left: 12px;
-}
diff --git a/src/__tests__/fixtures/optimiseMarginLonghand2.expected.css b/src/__tests__/fixtures/optimiseMarginLonghand2.expected.css
deleted file mode 100644
index 60f66324a..000000000
--- a/src/__tests__/fixtures/optimiseMarginLonghand2.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-h1{margin:9px 10px}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/optimiseMarginLonghand2.fixture.css b/src/__tests__/fixtures/optimiseMarginLonghand2.fixture.css
deleted file mode 100644
index d34970f34..000000000
--- a/src/__tests__/fixtures/optimiseMarginLonghand2.fixture.css
+++ /dev/null
@@ -1,6 +0,0 @@
-h1 {
-    margin-top: 9px;
-    margin-right: 10px;
-    margin-bottom: 9px;
-    margin-left: 10px;
-}
diff --git a/src/__tests__/fixtures/optimiseMarginLonghand3.expected.css b/src/__tests__/fixtures/optimiseMarginLonghand3.expected.css
deleted file mode 100644
index e893949b6..000000000
--- a/src/__tests__/fixtures/optimiseMarginLonghand3.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-h1{margin-top:8px;margin-right:12px!important;margin-bottom:14px;margin-left:10px!important}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/optimiseMarginLonghand3.fixture.css b/src/__tests__/fixtures/optimiseMarginLonghand3.fixture.css
deleted file mode 100644
index c80d2906a..000000000
--- a/src/__tests__/fixtures/optimiseMarginLonghand3.fixture.css
+++ /dev/null
@@ -1,6 +0,0 @@
-h1 {
-    margin-top: 8px;
-    margin-right: 12px !important;
-    margin-bottom: 14px;
-    margin-left: 10px !important;
-}
diff --git a/src/__tests__/fixtures/optimiseMarginShorthand.expected.css b/src/__tests__/fixtures/optimiseMarginShorthand.expected.css
deleted file mode 100644
index 6379b4aa4..000000000
--- a/src/__tests__/fixtures/optimiseMarginShorthand.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-h1{margin:10px 20px 30px 40px}h2{margin:10px 20px 30px}h3{margin:10px 20px}h4{margin:10px}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/optimiseMarginShorthand.fixture.css b/src/__tests__/fixtures/optimiseMarginShorthand.fixture.css
deleted file mode 100644
index c29b0ec86..000000000
--- a/src/__tests__/fixtures/optimiseMarginShorthand.fixture.css
+++ /dev/null
@@ -1,19 +0,0 @@
-h1 {
-    /* No expected optimisation */
-    margin: 10px 20px 30px 40px;
-}
-
-h2 {
-    /* Expected to transform to 3 values */
-    margin: 10px 20px 30px 20px;
-}
-
-h3 {
-    /* Expected to transform to 2 values */
-    margin: 10px 20px 10px 20px;
-}
-
-h4 {
-    /* Expected to transform to 1 value */
-    margin: 10px 10px 10px 10px;
-}
diff --git a/src/__tests__/fixtures/optimisePaddingLonghand.expected.css b/src/__tests__/fixtures/optimisePaddingLonghand.expected.css
deleted file mode 100644
index ed6e51100..000000000
--- a/src/__tests__/fixtures/optimisePaddingLonghand.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-div{padding:3px 4px 2px 1px}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/optimisePaddingLonghand.fixture.css b/src/__tests__/fixtures/optimisePaddingLonghand.fixture.css
deleted file mode 100644
index 4087977d2..000000000
--- a/src/__tests__/fixtures/optimisePaddingLonghand.fixture.css
+++ /dev/null
@@ -1,6 +0,0 @@
-div {
-    padding-left: 1px;
-    padding-bottom: 2px;
-    padding-top: 3px;
-    padding-right: 4px;
-}
diff --git a/src/__tests__/fixtures/preserveCalcSpaces.expected.css b/src/__tests__/fixtures/preserveCalcSpaces.expected.css
deleted file mode 100644
index 5980e1f6d..000000000
--- a/src/__tests__/fixtures/preserveCalcSpaces.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-div{width:calc(100vw / 2 - 6px + 0)}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/preserveCalcSpaces.fixture.css b/src/__tests__/fixtures/preserveCalcSpaces.fixture.css
deleted file mode 100644
index 78a6cd5eb..000000000
--- a/src/__tests__/fixtures/preserveCalcSpaces.fixture.css
+++ /dev/null
@@ -1,3 +0,0 @@
-div {
-    width: calc(100vw / 2 - 6px + 0);
-}
diff --git a/src/__tests__/fixtures/reduceCalc.disabled.css b/src/__tests__/fixtures/reduceCalc.disabled.css
deleted file mode 100644
index 82521376d..000000000
--- a/src/__tests__/fixtures/reduceCalc.disabled.css
+++ /dev/null
@@ -1 +0,0 @@
-h1{width:calc(3px * 2 - 1px)}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/reduceCalc.expected.css b/src/__tests__/fixtures/reduceCalc.expected.css
deleted file mode 100644
index a033eb34d..000000000
--- a/src/__tests__/fixtures/reduceCalc.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-h1{width:5px}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/reduceCalc.fixture.css b/src/__tests__/fixtures/reduceCalc.fixture.css
deleted file mode 100644
index 4c205efab..000000000
--- a/src/__tests__/fixtures/reduceCalc.fixture.css
+++ /dev/null
@@ -1,3 +0,0 @@
-h1 {
-    width: calc(3px * 2 - 1px);
-}
diff --git a/src/__tests__/fixtures/urlInsideString.expected.css b/src/__tests__/fixtures/urlInsideString.expected.css
deleted file mode 100644
index e0ae50f28..000000000
--- a/src/__tests__/fixtures/urlInsideString.expected.css
+++ /dev/null
@@ -1 +0,0 @@
-.box{background-image:url("data:image/svg+xml;charset=utf-8,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 1 1' preserveAspectRatio='none'%3E%3ClinearGradient id='a' gradientUnits='userSpaceOnUse' x1='0%25' y1='0%25' y2='0%25'%3E%3Cstop offset='0%25' stop-color='%23414042'/%3E%3Cstop offset='100%25' stop-color='%23fff' stop-opacity='0'/%3E%3C/linearGradient%3E%3Cpath fill='url(%23a)' d='M0 0h1v1H0z'/%3E%3C/svg%3E")}
\ No newline at end of file
diff --git a/src/__tests__/fixtures/urlInsideString.fixture.css b/src/__tests__/fixtures/urlInsideString.fixture.css
deleted file mode 100644
index 93ed4abeb..000000000
--- a/src/__tests__/fixtures/urlInsideString.fixture.css
+++ /dev/null
@@ -1,3 +0,0 @@
-.box {
-    background-image: url('data:image/svg+xml,%3C%3Fxml%20version%3D%221.0%22%20%3F%3E%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20version%3D%221.1%22%20width%3D%22100%25%22%20height%3D%22100%25%22%20viewBox%3D%220%200%201%201%22%20preserveAspectRatio%3D%22none%22%3E%3ClinearGradient%20id%3D%22gradient%22%20gradientUnits%3D%22userSpaceOnUse%22%20x1%3D%220%25%22%20y1%3D%220%25%22%20x2%3D%22100%25%22%20y2%3D%220%25%22%3E%3Cstop%20offset%3D%220%25%22%20stop-color%3D%22%23414042%22%2F%3E%3Cstop%20offset%3D%22100%25%22%20stop-color%3D%22%23ffffff%22%20stop-opacity%3D%220%22%2F%3E%3C%2FlinearGradient%3E%3Crect%20x%3D%220%22%20y%3D%220%22%20width%3D%221%22%20height%3D%221%22%20fill%3D%22url(%23gradient)%22%20%2F%3E%3C%2Fsvg%3E');
-}