1 files changed, 66 insertions, 0 deletions
diff --git a/third_party/python/pip_tools/piptools/exceptions.py b/third_party/python/pip_tools/piptools/exceptions.py
new file mode 100644
index 0000000000..5278972741
--- /dev/null
+++ b/third_party/python/pip_tools/piptools/exceptions.py
@@ -0,0 +1,66 @@
+from pip._internal.utils.misc import redact_auth_from_url
+
+
+class PipToolsError(Exception):
+    pass
+
+
+class NoCandidateFound(PipToolsError):
+    def __init__(self, ireq, candidates_tried, finder):
+        self.ireq = ireq
+        self.candidates_tried = candidates_tried
+        self.finder = finder
+
+    def __str__(self):
+        versions = []
+        pre_versions = []
+
+        for candidate in sorted(self.candidates_tried):
+            version = str(candidate.version)
+            if candidate.version.is_prerelease:
+                pre_versions.append(version)
+            else:
+                versions.append(version)
+
+        lines = ["Could not find a version that matches {}".format(self.ireq)]
+
+        if versions:
+            lines.append("Tried: {}".format(", ".join(versions)))
+
+        if pre_versions:
+            if self.finder.allow_all_prereleases:
+                line = "Tried"
+            else:
+                line = "Skipped"
+
+            line += " pre-versions: {}".format(", ".join(pre_versions))
+            lines.append(line)
+
+        if versions or pre_versions:
+            lines.append(
+                "There are incompatible versions in the resolved dependencies:"
+            )
+            source_ireqs = getattr(self.ireq, "_source_ireqs", [])
+            lines.extend("  {}".format(ireq) for ireq in source_ireqs)
+        else:
+            redacted_urls = tuple(
+                redact_auth_from_url(url) for url in self.finder.index_urls
+            )
+            lines.append("No versions found")
+            lines.append(
+                "{} {} reachable?".format(
+                    "Were" if len(redacted_urls) > 1 else "Was",
+                    " or ".join(redacted_urls),
+                )
+            )
+        return "\n".join(lines)
+
+
+class IncompatibleRequirements(PipToolsError):
+    def __init__(self, ireq_a, ireq_b):
+        self.ireq_a = ireq_a
+        self.ireq_b = ireq_b
+
+    def __str__(self):
+        message = "Incompatible requirements found: {} and {}"
+        return message.format(self.ireq_a, self.ireq_b)