From d0dd2cff1750909d75e948fe513ad3a7727dd5b3 Mon Sep 17 00:00:00 2001
From: Nicolo P <nicolo.paraciani@cnr.it>
Date: Wed, 16 Feb 2022 09:47:56 +0100
Subject: [PATCH] Fix stupid bug with ignore-case

---
 README.md              | 21 +++++++++++----------
 crapgrep/crapgrep.py   | 36 ++++++++++++++----------------------
 crapgrep/exceptions.py |  4 ++--
 3 files changed, 27 insertions(+), 34 deletions(-)

diff --git a/README.md b/README.md
index 81114e4..cd37630 100644
--- a/README.md
+++ b/README.md
@@ -6,20 +6,21 @@ Then this is for you...
 
 ## What is this?
 
-`crapgrep` is a poor imitation of the Unix utility `grep` written in Python.  
+`crapgrep` is a poor imitation of the Unix utility `grep`, written in Python.
+
 More specifically, it's a command line tool to search for a pattern or a substring in each line of one or more text files.
 
-The command synopsis is very similar to `grep`, although it needs the Python interpreter to be invoked explicitly (at the moment, at least):
+The command synopsis is very similar to `grep`'s, although it needs the Python interpreter to be invoked explicitly (at the moment, at least):
 
 ```
-python crapgrep.py [OPTIONS] [PATTERN] [FILE[...]]
+python crapgrep.py [OPTION...] [PATTERN] [FILE...]
 ```
 
-_**Note**: obviously, `crapgrep` doesn't read from `stdin`, which makes it even more useless..._
+> _**Note**: obviously, `crapgrep` doesn't read from `stdin`, which makes it even more useless..._
 
 ## Installation
 
-If you like wasting time because apparently you have nothing better to do, you can try `crapgrep` by cloning the repository with `git`:
+If you like wasting time (because apparently you have nothing better to do), you can try `crapgrep` by cloning the repository with `git`:
 
 ```bash
 git clone https://baltig.cnr.it/nicolo.paraciani/crapgrep.git
@@ -28,8 +29,8 @@ git clone https://baltig.cnr.it/nicolo.paraciani/crapgrep.git
 then
 
 ```bash
-cd crapgrep
-python crapgrep.py <option> <file(s)>
+cd crapgrep/crapgrep
+python crapgrep.py <options> <files>
 ```
 
 ## Examples
@@ -44,15 +45,15 @@ Searching for the simple string `'hola'` in file `garbage.txt` in the current di
 python crapgrep.py hola garbage.txt
 ```
 
-To make the search case-insensitive, you could do:
+To make the search case-insensitive:
 
 ```
-python crapgrep.py -i hOlA garbage.txt
+python crapgrep.py -i hola garbage.txt
 ```
 
 ### Regexp
 
-_**Note**: unlike `grep`, `crapgrep` doesn't treat the string as a regular expression pattern by default, it must be specified by passing the `-E` option explicitly._ 
+_**Note**: unlike `grep`, `crapgrep` doesn't treat the pattern as a regular expression by default, it must be specified by passing the `-E` option explicitly._ 
 
 Searching for pattern `'^urka[0-9]'` in files `garbage1.txt` and `garbage2.txt` in the parent directory:
 
diff --git a/crapgrep/crapgrep.py b/crapgrep/crapgrep.py
index 27309ed..14ffffe 100644
--- a/crapgrep/crapgrep.py
+++ b/crapgrep/crapgrep.py
@@ -2,11 +2,9 @@ import exceptions
 import re
 import os
 import sys
-import sty
 
 
-# TODO Avoid extra fname argument??
-def find_line(line: str, pattern: str, is_regexp=False) -> bool:
+def find_line(line: str, pattern: str, i_case: bool, is_regexp=False) -> bool:
     """
     Distinguish between regexp or not (default is False)
     """
@@ -16,6 +14,9 @@ def find_line(line: str, pattern: str, is_regexp=False) -> bool:
     if is_regexp:
         matches = re.findall(pattern, line)
         FIND_COND = len(matches) > 0
+    elif i_case:
+        lower = line.lower()
+        FIND_COND = lower.find(pattern.lower()) != -1
     else:
         FIND_COND = line.find(pattern) != -1
 
@@ -93,7 +94,7 @@ def parse_args(args: list) -> dict:
     # TODO does it make sense?
     for opt in options:
         if opt not in OPTS:
-            raise exceptions.InvalidOption(opt[1:])
+            raise exceptions.InvalidOptionError(opt)
 
     args_tree["options"] = options
 
@@ -113,22 +114,13 @@ def parse_args(args: list) -> dict:
     return args_tree
 
 
-def match_regexp(pattern: str, line: str) -> object:
-    """
-    Search for pattern in the given line and return
-    a match object or None if no match found.
-
-    Flags??
-    """
-    return re.search(pattern, line)
-
-
 def process_grep(args_tree: dict) -> list:
     lines = []
     found_lines = []
     options = args_tree["options"]
     pattern = args_tree["pattern"]
     files = args_tree["files"]
+    i_case = False
 
     try:
         for f in files:
@@ -139,19 +131,19 @@ def process_grep(args_tree: dict) -> list:
 
             n = 0
 
-            # Check if case insensitive
-            if 'i' in options:
-                pattern = pattern.lower()
             for line in lines:
                 n = n + 1
+                # Check if case insensitive
+                if 'i' in options:
+                    i_case = True
                 # Check if regexp flag
                 if 'E' in options:
                     # pattern is regexp
                     if not check_pattern(pattern):
-                        raise exceptions.InvalidPattern(pattern)
-                    found = find_line(line, pattern, True)
+                        raise exceptions.InvalidPatternError(pattern)
+                    found = find_line(line, pattern, i_case, True)
                 else:
-                    found = find_line(line, pattern)
+                    found = find_line(line, pattern, i_case)
 
                 lnum = str(n) + ':' if 'n' in options else ''
 
@@ -175,7 +167,7 @@ if __name__ == "__main__":
 
     try:
         args_tree = parse_args(args)
-    except exceptions.InvalidOption as e:
+    except exceptions.InvalidOptionError as e:
         print(e.get_message())
         print_usage()
         sys.exit(1)
@@ -183,6 +175,6 @@ if __name__ == "__main__":
     try:
         for line in process_grep(args_tree):
             print(line)
-    except exceptions.InvalidPattern as e:
+    except exceptions.InvalidPatternError as e:
         print(e.get_message())
         sys.exit(1)
diff --git a/crapgrep/exceptions.py b/crapgrep/exceptions.py
index ff1ae4a..8fe2fc2 100644
--- a/crapgrep/exceptions.py
+++ b/crapgrep/exceptions.py
@@ -1,4 +1,4 @@
-class InvalidOption(Exception):
+class InvalidOptionError(Exception):
     def __init__(self, invalid_opt):
         self.invalid_opt = invalid_opt
 
@@ -6,7 +6,7 @@ class InvalidOption(Exception):
         return f"crapgrep: invalid option -- '{self.invalid_opt}'"
 
 
-class InvalidPattern(Exception):
+class InvalidPatternError(Exception):
     def __init__(self, pattern):
         self.invalid = pattern