This report only describes that an enchantment is shown which is not available. See MC-30730, which describes the general behavior that an enchantment table may provide less than three enchantments.
The bug
When enchanting fishing rods, you are not able to apply low level enchants; the bug here is that these enchants still appear as if they could be selected. They should be greyed out.
See attached
[media]: The first slot, which the mouse is hovering over, does not display any promised enchant in the tooltip and clicking it does nothing, yet it's not greyed out like the middle slot.
Example
Here is an example in video:
[media]Bug analysis
@unknown has done a detailed analysis of when the bug occurs and possible solutions in this comment.
Code analysis
The following is based on decompiled version of Minecraft 1.9 using MCP 9.24 beta. All method and class names are the names used in the decompiled version.
The reason why this happens is because the enchantment level returned by the method net.minecraft.enchantment.EnchantmentHelper.calcItemStackEnchantability(Random, int, int, ItemStack) is used. This method always returns at least 1 for the first enchantment (0 meaning no enchantment available). I am not sure if this can be fixed in this method, however what can be done is having the method net.minecraft.inventory.ContainerEnchantment.onCraftMatrixChanged(IInventory) set 0 as enchantment level if no enchantments are available.
This might not be the best solution and is only a suggestion.
Linked issues
is duplicated by 82
MC-50844
Damaged Fishing Rods not able to be enchanted
Resolved
MC-72819
Fishing Rod seems to break enchanting.
Resolved
MC-84953
Enchanting uses levels but does not apply them to item placed on the enchantment table.
Resolved
MC-85339
Enchanting a fishing rod no enchant
Resolved
MC-91812
Enchanting fishing rod with levels < 4 eats up level and lapis
Resolved
relates to 3
Attachments
Comments 39
Is this still a concern in the current Minecraft version 14w20b / Launcher version 1.3.11 or later? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.
Please link to this comment in the description
The following is based on decompiled version of Minecraft 1.9 using MCP 9.24 beta. All method and class names are the names used in the decompiled version.
The reason why this happens is because the enchantment level returned by the method net.minecraft.enchantment.EnchantmentHelper.calcItemStackEnchantability(Random, int, int, ItemStack) is used. This method always returns at least 1 for the first enchantment (0 meaning no enchantment available). I am not sure if this can be fixed in this method, however what can be done is having the method net.minecraft.inventory.ContainerEnchantment.onCraftMatrixChanged(IInventory) set 0 as enchantment level if no enchantments are available.
This might not be the best solution and is only a suggestion.
Please create a separate ticket regarding maces.
Edit: MC-273234
Confirmed for 14w11b. First I've heard of it but it was so quick to playtest I thought "why not check".