test parsepath

tools/random_parse_path.cpp

Index: tools/random_parse_path.cpp
diff --git a/tools/random_parse_path.cpp b/tools/random_parse_path.cpp
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index 0000000000000000000000000000000000000000..ffc4b58ef6ec2d99746be0336ff8b1aaf479493d
--- /dev/null
+++ b/tools/random_parse_path.cpp
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+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkRandom.h"
+#include "random_parse_path.h"
+
+const struct Legal {
+    char fSymbol;
+    int fScalars;
+} gLegal[] = {
+    { 'M', 2 },
+    { 'H', 1 },
+    { 'V', 1 },
+    { 'L', 2 },
+    { 'Q', 4 },
+    { 'T', 2 },
+    { 'C', 6 },
+    { 'S', 4 },
+    { 'A', 4 },
+    { 'Z', 0 },
+};
+
+bool gEasy = false;  // set to true while debugging to suppress unusual whitespace
+
+// mostly do nothing, then bias towards spaces
+const char gWhiteSpace[] = { 0, 0, 0, 0, 0, 0, 0, 0, ' ', ' ', ' ', ' ', 0x09, 0x0D, 0x0A };
+
+static void add_white(SkRandom* rand, SkString* atom) {
+    if (gEasy) {
+        atom->append(" ");
+        return;
+    }
+    int reps = rand->nextRangeU(0, 2);
+    for (int rep = 0; rep < reps; ++rep) {
+        int index = rand->nextRangeU(0, (int) SK_ARRAY_COUNT(gWhiteSpace) - 1);
+        if (gWhiteSpace[index]) {
+            atom->append(&gWhiteSpace[index], 1);
+        }
+    }
+}
+
+static void add_comma(SkRandom* rand, SkString* atom) {
+    if (gEasy) {
+        atom->append(",");
+        return;
+    }
+    size_t count = atom->size();
+    add_white(rand, atom);
+    if (rand->nextBool()) {
+        atom->append(",");
+    }
+    do {
+        add_white(rand, atom);
+    } while (count == atom->size());
+}
+
+static void add_some_white(SkRandom* rand, SkString* atom) {
+    size_t count = atom->size();
+    do {
+        add_white(rand, atom);
+    } while (count == atom->size());
+}
+
+SkString MakeRandomParsePathPiece(SkRandom* rand) {
+    SkString atom;
+    int index = rand->nextRangeU(0, (int) SK_ARRAY_COUNT(gLegal) - 1);
+    const Legal& legal = gLegal[index];
+    gEasy ? atom.append("\n") : add_white(rand, &atom);
+    char symbol = legal.fSymbol | (rand->nextBool() ? 0x20 : 0);
+    atom.append(&symbol, 1);
+    int reps = rand->nextRangeU(1, 3);
+    for (int rep = 0; rep < reps; ++rep) {
+        for (int index = 0; index < legal.fScalars; ++index) {
+            SkScalar coord = rand->nextRangeF(0, 100);
+            add_white(rand, &atom);
+            atom.appendScalar(coord);
+            if (rep < reps - 1 && index < legal.fScalars - 1) {
+                add_comma(rand, &atom);
+            } else {
+                add_some_white(rand, &atom);
+            }
+            if ('A' == legal.fSymbol && 1 == index) {
+                atom.appendScalar(rand->nextRangeF(-720, 720));
+                add_comma(rand, &atom);
+                atom.appendU32(rand->nextRangeU(0, 1));
+                add_comma(rand, &atom);
+                atom.appendU32(rand->nextRangeU(0, 1));
+                add_comma(rand, &atom);
+            }
+        }
+    }
+    return atom;
+}