Auto merge of #5805 - pcwalton:whitespace-effect-on-minimum-inline-sizes, r=glennw

Improves Amazon.

r? @glennw

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components/layout/fragment.rs

@@ -16,8 +16,7 @@ use flow_ref::FlowRef;
 use incremental::{self, RestyleDamage};
 use inline::{InlineFragmentContext, InlineMetrics};
 use layout_debug;
-use model::{IntrinsicISizes, IntrinsicISizesContribution, MaybeAuto, specified};
+use model::{self, IntrinsicISizes, IntrinsicISizesContribution, MaybeAuto, specified};
-use model;
 use text;
 use opaque_node::OpaqueNodeMethods;
 use wrapper::{TLayoutNode, ThreadSafeLayoutNode};
@@ -1200,7 +1199,6 @@ impl Fragment {
             }
             SpecificFragmentInfo::ScannedText(ref text_fragment_info) => {
                 let range = &text_fragment_info.range;
-                let min_line_inline_size = text_fragment_info.run.min_width_for_range(range);
 
                 // See http://dev.w3.org/csswg/css-sizing/#max-content-inline-size.
                 // TODO: Account for soft wrap opportunities.
@@ -1208,6 +1206,11 @@ impl Fragment {
                                                              .metrics_for_range(range)
                                                              .advance_width;
 
+                let min_line_inline_size = match self.style.get_inheritedtext().white_space {
+                    white_space::T::pre | white_space::T::nowrap => max_line_inline_size,
+                    white_space::T::normal => text_fragment_info.run.min_width_for_range(range),
+                };
+
                 result.union_block(&IntrinsicISizes {
                     minimum_inline_size: min_line_inline_size,
                     preferred_inline_size: max_line_inline_size,

components/layout/inline.rs

@@ -1133,12 +1133,49 @@ impl Flow for InlineFlow {
             flow::mut_base(kid).floats = Floats::new(writing_mode);
         }
 
-        let mut computation = IntrinsicISizesContribution::new();
+        let mut intrinsic_sizes_for_flow = IntrinsicISizesContribution::new();
+        let mut intrinsic_sizes_for_inline_run = IntrinsicISizesContribution::new();
+        let mut intrinsic_sizes_for_nonbroken_run = IntrinsicISizesContribution::new();
         for fragment in self.fragments.fragments.iter_mut() {
-            debug!("Flow: measuring {:?}", *fragment);
+            let intrinsic_sizes_for_fragment = fragment.compute_intrinsic_inline_sizes().finish();
-            computation.union_inline(&fragment.compute_intrinsic_inline_sizes().finish())
+            match fragment.style.get_inheritedtext().white_space {
+                white_space::T::nowrap => {
+                    intrinsic_sizes_for_nonbroken_run.union_nonbreaking_inline(
+                        &intrinsic_sizes_for_fragment)
+                }
+                white_space::T::pre => {
+                    intrinsic_sizes_for_nonbroken_run.union_nonbreaking_inline(
+                        &intrinsic_sizes_for_fragment);
+
+                    // Flush the intrinsic sizes we've been gathering up in order to handle the
+                    // line break, if necessary.
+                    if fragment.requires_line_break_afterward_if_wrapping_on_newlines() {
+                        intrinsic_sizes_for_inline_run.union_inline(
+                            &intrinsic_sizes_for_nonbroken_run.finish());
+                        intrinsic_sizes_for_nonbroken_run = IntrinsicISizesContribution::new();
+                        intrinsic_sizes_for_flow.union_block(
+                            &intrinsic_sizes_for_inline_run.finish());
+                        intrinsic_sizes_for_inline_run = IntrinsicISizesContribution::new();
+                    }
+                }
+                white_space::T::normal => {
+                    // Flush the intrinsic sizes we were gathering up for the nonbroken run, if
+                    // necessary.
+                    intrinsic_sizes_for_inline_run.union_inline(
+                        &intrinsic_sizes_for_nonbroken_run.finish());
+                    intrinsic_sizes_for_nonbroken_run = IntrinsicISizesContribution::new();
+
+                    intrinsic_sizes_for_nonbroken_run.union_inline(&intrinsic_sizes_for_fragment)
+                }
+            }
         }
-        self.base.intrinsic_inline_sizes = computation.finish()
+
+        // Flush any remaining nonbroken-run and inline-run intrinsic sizes.
+        intrinsic_sizes_for_inline_run.union_inline(&intrinsic_sizes_for_nonbroken_run.finish());
+        intrinsic_sizes_for_flow.union_block(&intrinsic_sizes_for_inline_run.finish());
+
+        // Finish up the computation.
+        self.base.intrinsic_inline_sizes = intrinsic_sizes_for_flow.finish()
     }
 
     /// Recursively (top-down) determines the actual inline-size of child contexts and fragments.

components/layout/model.rs

@@ -331,6 +331,17 @@ impl IntrinsicISizesContribution {
             self.content_intrinsic_sizes.preferred_inline_size + sizes.preferred_inline_size
     }
 
+    /// Updates the computation so that the minimum is the sum of the current minimum and the
+    /// given minimum and the preferred is the sum of the current preferred and the given
+    /// preferred. This is used when laying out fragments in the inline direction when
+    /// `white-space` is `pre` or `nowrap`.
+    pub fn union_nonbreaking_inline(&mut self, sizes: &IntrinsicISizes) {
+        self.content_intrinsic_sizes.minimum_inline_size =
+            self.content_intrinsic_sizes.minimum_inline_size + sizes.minimum_inline_size;
+        self.content_intrinsic_sizes.preferred_inline_size =
+            self.content_intrinsic_sizes.preferred_inline_size + sizes.preferred_inline_size
+    }
+
     /// Updates the computation so that the minimum is the maximum of the current minimum and the
     /// given minimum and the preferred is the maximum of the current preferred and the given
     /// preferred. This can be useful when laying out fragments in the block direction (but note

tests/ref/white_space_intrinsic_sizes_a.html

@@ -0,0 +1,50 @@
+<!DOCTYPE html>
+<html>
+<head>
+<style type="text/css">
+    table {
+        width: 0;
+    }
+    td {
+        border: solid black 1px;
+        white-space: nowrap;
+    }
+</style>
+</head>
+
+<body>
+    <table>
+        <tr>
+            <td>
+                <div>
+                    <div>Instant Video</div>
+                </div>
+            </td>
+
+            <td>
+                <div>
+                    <div>Digital Music Store</div>
+                </div>
+            </td>
+
+            <td>
+                <div>
+                    <div>Cloud Drive</div>
+                </div>
+            </td>
+
+            <td>
+                <div>
+                    <div>Fire Phone</div>
+                </div>
+            </td>
+
+            <td>
+                <div>
+                    <div>Appstore<br>for Android</div>
+                </div>
+            </td>
+        </tr>
+    </table>
+</body>
+</html>

tests/ref/white_space_intrinsic_sizes_ref.html

@@ -0,0 +1,46 @@
+<!DOCTYPE html>
+<html>
+<head>
+<style type="text/css">
+    td {
+        border: solid black 1px;
+    }
+</style>
+</head>
+
+<body>
+    <table>
+        <tr>
+            <td>
+                <div>
+                    <div>Instant&nbsp;Video</div>
+                </div>
+            </td>
+
+            <td>
+                <div>
+                    <div>Digital&nbsp;Music&nbsp;Store</div>
+                </div>
+            </td>
+
+            <td>
+                <div>
+                    <div>Cloud&nbsp;Drive</div>
+                </div>
+            </td>
+
+            <td>
+                <div>
+                    <div>Fire&nbsp;Phone</div>
+                </div>
+            </td>
+
+            <td>
+                <div>
+                    <div><div>Appstore</div><div>for Android</div></div>
+                </div>
+            </td>
+        </tr>
+    </table>
+</body>
+</html>