From 9de471a0f4bea20581034c2d74b0652c27e0fad0 Mon Sep 17 00:00:00 2001
From: Bogdan Chadkin <trysound@yandex.ru>
Date: Wed, 24 Feb 2021 00:58:11 +0300
Subject: [PATCH] Handle nested textual tags

This bug was also catched by regression tests. Single state was
overriden in opentag/closetag callbacks. Using stack state solved the
problem with nested textual tags.

Now many whitespaces bugs should go away.
---
 lib/svgo/svg2js.js        | 36 +++++++++---------------------------
 test/svgo/_index.js       |  5 +++++
 test/svgo/whitespaces.svg | 15 +++++++++++++++
 3 files changed, 29 insertions(+), 27 deletions(-)
 create mode 100644 test/svgo/whitespaces.svg

diff --git a/lib/svgo/svg2js.js b/lib/svgo/svg2js.js
index f1ff513c5..bdf9c6d4d 100644
--- a/lib/svgo/svg2js.js
+++ b/lib/svgo/svg2js.js
@@ -26,8 +26,7 @@ module.exports = function(data) {
     var sax = SAX.parser(config.strict, config),
         root = new JSAPI({ elem: '#document', content: [] }),
         current = root,
-        stack = [root],
-        textContext = null;
+        stack = [root];
 
     function pushToContent(content) {
 
@@ -116,39 +115,22 @@ module.exports = function(data) {
         elem = pushToContent(elem);
         current = elem;
 
-        // Save info about tags containing text to prevent trimming of meaningful whitespace
-        if (textElems.includes(data.name) && !data.prefix) {
-            textContext = current;
-        }
-
         stack.push(elem);
 
     };
 
     sax.ontext = function(text) {
-
-        if (/\S/.test(text) || textContext) {
-
-            if (!textContext)
-                text = text.trim();
-
-            pushToContent({
-                text: text
-            });
-
-        }
-
+      // prevent trimming of meaningful whitespace inside textual tags
+      if (textElems.includes(current.elem) && !data.prefix) {
+        pushToContent({ text: text });
+      } else if (/\S/.test(text)) {
+        pushToContent({ text: text.trim() });
+      }
     };
 
     sax.onclosetag = function() {
-
-        var last = stack.pop();
-
-        if (last == textContext) {
-            textContext = null;
-        }
-        current = stack[stack.length - 1];
-
+      stack.pop();
+      current = stack[stack.length - 1];
     };
 
     sax.onerror = function(e) {
diff --git a/test/svgo/_index.js b/test/svgo/_index.js
index 4d5d9d4ae..f0f8906ad 100644
--- a/test/svgo/_index.js
+++ b/test/svgo/_index.js
@@ -71,4 +71,9 @@ describe('svgo', () => {
     const result = optimize(original, { path: 'input.svg', plugins: [], js2svg: { pretty: true } });
     expect(normalize(result.data)).to.equal(expected);
   });
+  it('should preserve whitespaces between tspan tags', async () => {
+    const [original, expected] = await parseFixture('whitespaces.svg');
+    const result = optimize(original, { path: 'input.svg', js2svg: { pretty: true } });
+    expect(normalize(result.data)).to.equal(expected);
+  });
 });
diff --git a/test/svgo/whitespaces.svg b/test/svgo/whitespaces.svg
new file mode 100644
index 000000000..fcc2895a1
--- /dev/null
+++ b/test/svgo/whitespaces.svg
@@ -0,0 +1,15 @@
+<svg width="480" height="360" xmlns="http://www.w3.org/2000/svg">
+  <text x="20" y="20">
+    <tspan>Another tspan</tspan>
+    <tspan>Inside tspan</tspan> - outside tspan
+  </text>
+</svg>
+
+@@@
+
+<svg width="480" height="360" xmlns="http://www.w3.org/2000/svg">
+    <text x="20" y="20">
+    <tspan>Another tspan</tspan>
+    <tspan>Inside tspan</tspan> - outside tspan
+  </text>
+</svg>