lib.uri: add {native,posix-extended}-regex

1 files changed, 77 insertions, 0 deletions

diff --git a/lib/uri.nix b/lib/uri.nix
new file mode 100644
index 000000000..72ad390b7
--- /dev/null
+++ b/lib/uri.nix
@@ -0,0 +1,77 @@
+{ lib }:
+with lib;
+with builtins;
+rec {
+  # Regular expression to match URIs per RFC3986
+  # From: # http://jmrware.com/articles/2009/uri_regexp/URI_regex.html#uri-40
+  native-regex = ''
+    # RFC-3986 URI component:  URI
+    [A-Za-z][A-Za-z0-9+\-.]* :                                      # scheme ":"
+    (?: //                                                          # hier-part
+      (?: (?:[A-Za-z0-9\-._~!$&'()*+,;=:]|%[0-9A-Fa-f]{2})* @)?
+      (?:
+        \[
+        (?:
+          (?:
+            (?:                                                    (?:[0-9A-Fa-f]{1,4}:){6}
+            |                                                   :: (?:[0-9A-Fa-f]{1,4}:){5}
+            | (?:                            [0-9A-Fa-f]{1,4})? :: (?:[0-9A-Fa-f]{1,4}:){4}
+            | (?: (?:[0-9A-Fa-f]{1,4}:){0,1} [0-9A-Fa-f]{1,4})? :: (?:[0-9A-Fa-f]{1,4}:){3}
+            | (?: (?:[0-9A-Fa-f]{1,4}:){0,2} [0-9A-Fa-f]{1,4})? :: (?:[0-9A-Fa-f]{1,4}:){2}
+            | (?: (?:[0-9A-Fa-f]{1,4}:){0,3} [0-9A-Fa-f]{1,4})? ::    [0-9A-Fa-f]{1,4}:
+            | (?: (?:[0-9A-Fa-f]{1,4}:){0,4} [0-9A-Fa-f]{1,4})? ::
+            ) (?:
+                [0-9A-Fa-f]{1,4} : [0-9A-Fa-f]{1,4}
+              | (?: (?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?) \.){3}
+                    (?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)
+              )
+          |   (?: (?:[0-9A-Fa-f]{1,4}:){0,5} [0-9A-Fa-f]{1,4})? ::    [0-9A-Fa-f]{1,4}
+          |   (?: (?:[0-9A-Fa-f]{1,4}:){0,6} [0-9A-Fa-f]{1,4})? ::
+          )
+        | [Vv][0-9A-Fa-f]+\.[A-Za-z0-9\-._~!$&'()*+,;=:]+
+        )
+        \]
+      | (?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}
+           (?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)
+      | (?:[A-Za-z0-9\-._~!$&'()*+,;=]|%[0-9A-Fa-f]{2})*
+      )
+      (?: : [0-9]* )?
+      (?:/ (?:[A-Za-z0-9\-._~!$&'()*+,;=:@]|%[0-9A-Fa-f]{2})* )*
+    | /
+      (?:    (?:[A-Za-z0-9\-._~!$&'()*+,;=:@]|%[0-9A-Fa-f]{2})+
+        (?:/ (?:[A-Za-z0-9\-._~!$&'()*+,;=:@]|%[0-9A-Fa-f]{2})* )*
+      )?
+    |        (?:[A-Za-z0-9\-._~!$&'()*+,;=:@]|%[0-9A-Fa-f]{2})+
+        (?:/ (?:[A-Za-z0-9\-._~!$&'()*+,;=:@]|%[0-9A-Fa-f]{2})* )*
+    |
+    )
+    (?:\? (?:[A-Za-z0-9\-._~!$&'()*+,;=:@/?]|%[0-9A-Fa-f]{2})* )?   # [ "?" query ]
+    (?:\# (?:[A-Za-z0-9\-._~!$&'()*+,;=:@/?]|%[0-9A-Fa-f]{2})* )?   # [ "#" fragment ]
+  '';
+
+  posix-extended-regex =
+    let
+      removeComment = s:
+        elemAt (match "^((\\\\#|[^#])*)(#.*)?$" s) 0;
+
+      removeWhitespace =
+        replaceStrings [" "] [""];
+
+      moveDashToEndOfCharacterClass = s:
+        let
+          result = match "(.*)\\\\-([^]]+)(].*)" s;
+          s' = elemAt result 0 + elemAt result 1 + "-" + elemAt result 2;
+        in
+          if result != null then
+            moveDashToEndOfCharacterClass s'
+          else
+            s;
+    in
+      concatStrings
+        (foldl' (a: f: map f a) (splitString "\n" native-regex) [
+          removeComment
+          moveDashToEndOfCharacterClass
+          (replaceStrings ["(?:"] ["("])
+          removeWhitespace
+        ]);
+}