From c6dbcda947211e4799b741378fe80931ae518c4e Mon Sep 17 00:00:00 2001
From: Daniil Fajnberg <mail@daniil.fajnberg.de>
Date: Sat, 1 Jan 2022 17:21:36 +0100
Subject: [PATCH] verbose error with wrong options

---
 setup.cfg                 |  2 +-
 src/yamlhttpforms/html.py | 16 +++++++++++++---
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/setup.cfg b/setup.cfg
index ad24362..9780042 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,6 +1,6 @@
 [metadata]
 name = yamlhttpforms
-version = 0.0.3
+version = 0.0.4
 author = Daniil F.
 author_email = mail@placeholder123.to
 description = HTTP forms defined in YAML
diff --git a/src/yamlhttpforms/html.py b/src/yamlhttpforms/html.py
index bcdc3f3..37610f7 100644
--- a/src/yamlhttpforms/html.py
+++ b/src/yamlhttpforms/html.py
@@ -45,9 +45,19 @@ def check_select_field_options(field_tag: Tag, field_interface: 'FormField', che
         `FieldInterfaceWrong`
             if the `default` is not equal to the value of the <option> tag which has the `selected` attribute
     """
-    options = {tag[VALUE]: tag.get_text(strip=True) for tag in field_tag.find_all(OPTION)}
-    if options != field_interface.options:
-        raise SelectOptionsWrong(f"Wrong options in {field_interface}")
+    html_options = {(tag[VALUE], tag.get_text(strip=True)) for tag in field_tag.find_all(OPTION)}
+    interface_options = set(field_interface.options.items())
+    missing_in_interface = html_options - interface_options
+    not_in_html = interface_options - html_options
+    s = ""
+    if missing_in_interface:
+        s += "\nThe following <options> HTML tags were not found in the interface:\n"
+        s += "\n".join(str(tup) for tup in missing_in_interface)
+    if not_in_html:
+        s += "\nThe following options were defined, but are not present in the HTML:\n"
+        s += "\n".join(str(tup) for tup in not_in_html)
+    if s:
+        raise SelectOptionsWrong(f"Wrong options in field '{field_interface.name}'." + s)
     if check_defaults:
         default = field_tag.find(lambda tag: tag.name == OPTION and tag.has_attr(SELECTED))[VALUE]
         if default != field_interface.default: